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help / color / mirror / Atom feedFrom: Amit Langote <[email protected]>
To: Tom Lane <[email protected]>
Cc: Tender Wang <[email protected]>
Cc: Alexander Lakhin <[email protected]>
Cc: Tomas Vondra <[email protected]>
Cc: Robert Haas <[email protected]>
Cc: Alvaro Herrera <[email protected]>
Cc: Andres Freund <[email protected]>
Cc: Daniel Gustafsson <[email protected]>
Cc: David Rowley <[email protected]>
Cc: PostgreSQL Hackers <[email protected]>
Cc: Thom Brown <[email protected]>
Subject: Re: generic plans and "initial" pruning
Date: Wed, 12 Nov 2025 23:17:43 +0900
Message-ID: <CA+HiwqEF9SgKyQ1HrYOURpv8DGRGHDNwBT9Y6yEBVCW+=kh_=w@mail.gmail.com> (raw)
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Hi,
On Tue, Jul 22, 2025 at 3:43 PM Amit Langote <[email protected]> wrote:
> On Thu, Jul 17, 2025 at 9:11 PM Amit Langote <[email protected]> wrote:
> > The refinements I described in my email above might help mitigate some
> > of those executor-related issues. However, I'm starting to wonder if
> > it's worth reconsidering our decision to handle pruning, locking, and
> > validation entirely at executor startup, which was the approach taken
> > in the reverted patch.
> >
> > The alternative approach, doing initial pruning and locking within
> > plancache.c itself (which I floated a while ago), might be worth
> > revisiting. It avoids the complications we've discussed around the
> > executor API and preserves the clear separation of concerns that
> > plancache.c provides, though it does introduce some new layering
> > concerns, which I describe further below.
> >
> > To support this, we'd need a mechanism to pass pruning results to the
> > executor alongside each PlannedStmt. For each PartitionPruneInfo in
> > the plan, that would include the corresponding PartitionPruneState and
> > the bitmapset of surviving relids determined by initial pruning. Given
> > that a CachedPlan can contain multiple PlannedStmts, this would
> > effectively be a list of pruning results, one per statement. One
> > reasonable way to handle that might be to define a parallel data
> > structure, separate from PlannedStmt, constructed by plancache.c and
> > carried via QueryDesc. The memory and lifetime management would mirror
> > how ParamListInfo is handled today, leaving the executor API unchanged
> > and avoiding intrusive changes to PlannedStmt.
> >
> > However, one potentially problematic aspect of this design is managing
> > the lifecycle of the relations referenced by PartitionPruneState.
> > Currently, partitioned table relations are opened by the executor
> > after entering ExecutorStart() and closed automatically by
> > ExecEndPlan(), allowing cleanup of pruning states implicitly. If we
> > perform initial pruning earlier, we'd need to keep these relations
> > open longer, necessitating explicit cleanup calls (e.g., a new
> > FinishPartitionPruneState()) invoked by the caller of the executor,
> > such as from ExecutorEnd() or even higher-level callers. This
> > introduces some questionable layering by shifting responsibility for
> > relation management tasks, which ideally belong within the executor,
> > into its callers.
> >
> > My sense is that the complexity involved in carrying pruning results
> > via this parallel data structure was one of the concerns Tom raised
> > previously, alongside the significant pruning code refactoring that
> > the earlier patch required. The latter, at least, should no longer be
> > necessary given recent code improvements.
>
> One point I forgot to mention about this approach is that we'd also
> need to ensure permissions on parent relations are checked before
> performing initial pruning in plancache.c, since pruning may involve
> evaluating user-provided expressions. So in effect, we'd need to
> invoke not just ExecDoInitialPruning(), but also
> ExecCheckPermissions(), or some variant of it, prior to executor
> startup. While manageable, it does add slightly to the complexity.
Sorry for the absence. I've now implemented the approach mentioned
above and split it into a series of reasonably isolated patches.
The key idea is to avoid taking unnecessary locks when reusing a
cached plan. To achieve that, we need to perform initial partition
pruning during cached plan reuse in plancache.c so that only surviving
partitions are locked. This requires some plumbing to reuse the result
of this "early" pruning during executor startup, because repeating the
pruning logic would be both inefficient and potentially inconsistent
-- what if you get different results the second time? (I don't have
proof that this can happen, but some earlier emails mention the
theoretical risk, so better to be safe.)
So this patch introduces ExecutorPrep(), which allows executor
metadata such as initial pruning results (valid subplan indexes) and
full unpruned_relids to be computed ahead of execution and reused
later by ExecutorStart() and during QueryDesc setup in parallel
workers using the results shared by the leader. The parallel query bit
was discussed previously at [1], though I didn’t have a solution I
liked then.
This revives an idea that was last implemented in the patch (v30)
posted on Dec 16, 2022. In retrospect, I understand the hesitation Tom
might have had about the patch at the time -- its changes to enable
early pruning and then feed the results into ExecutorStart() were less
than pretty. Thanks to the initial pruning code refactoring that I
committed in Postgres 18, those changes now seem much more principled
and modular IMO.
The patch set is structured as follows:
* Refactor partition pruning initialization (0001): separates the
setup of the pruning state from its execution by introducing
ExecCreatePartitionPruneStates(). This makes the pruning logic easier
to reuse and adds flexibility to do only the setup but skip pruning in
some cases.
* Introduce ExecutorPrep infrastructure (0002): adds ExecutorPrep()
and ExecPrep as a formal way to perform executor setup ahead of
execution. This enables caching or transferring pruning results and
other metadata without triggering execution. ExecutorStart() can now
consume precomputed prep state from the EState created during
ExecutorPrep(). ExecPrepCleanup() handles cleanup when the plan is
invalidated during prep and so not executed; the state is cleaned up
in the regular ExecutorEnd() path otherwise.
* Allow parallel workers to reuse leader pruning results (0003): lets
workers reuse the leader’s initial pruning results (valid subplan
indexes) and unpruned_relids via ExecutorPrep(). This adds a
verification step to check that leader and worker decisions match,
throwing an error if they don’t -- so "reuse" is a bit of a lie.
Should that check be debug-only? (Maybe not.) As mentioned above, this
was previously discussed at [1].
* Enable pruning-aware locking in cached / generic plan reuse (0004):
extends GetCachedPlan() and CheckCachedPlan() to call ExecutorPrep()
on each PlannedStmt in the CachedPlan, locking only surviving
partitions. Adds CachedPlanPrepData to pass this through plan cache
APIs and down to execution via QueryDesc. Also reinstates the
firstResultRel locking rule added in 28317de72 but later lost due to
revert of the earlier pruning patch, to ensure correctness when all
target partitions are pruned.
This approach keeps plan caching and validation logic self-contained
in plancache.c, avoids invasive executor API changes.
Benchmark results:
echo "plan_cache_mode = force_generic_plan" >> $PGDATA/postgresql.conf
for p in 32 64 128 256 512 1024; do pgbench -i --partitions=$p >
/dev/null 2>&1; echo -ne "$p\t"; pgbench -n -S -T10 -Mprepared | grep
tps; done
Master
32 tps = 23841.822407 (without initial connection time)
64 tps = 21578.619816 (without initial connection time)
128 tps = 18090.500707 (without initial connection time)
256 tps = 14152.248201 (without initial connection time)
512 tps = 9432.708423 (without initial connection time)
1024 tps = 5873.696475 (without initial connection time)
Patched
32 tps = 24724.245798 (without initial connection time)
64 tps = 24858.206407 (without initial connection time)
128 tps = 24652.655269 (without initial connection time)
256 tps = 23656.756615 (without initial connection time)
512 tps = 22299.865769 (without initial connection time)
1024 tps = 21911.704317 (without initial connection time)
Comments welcome.
[1] https://www.postgresql.org/message-id/CA%2BHiwqFA%3DswkzgGK8AmXUNFtLeEXFJwFyY3E7cTxvL46aa1OTw%40mail...
--
Thanks, Amit Langote
Attachments:
[application/octet-stream] v1-0003-Reuse-partition-pruning-results-in-parallel-worke.patch (9.0K, 2-v1-0003-Reuse-partition-pruning-results-in-parallel-worke.patch)
download | inline diff:
From d23a05d6f412dcbfd38a910331527765999d78e9 Mon Sep 17 00:00:00 2001
From: Amit Langote <[email protected]>
Date: Tue, 11 Nov 2025 22:17:47 +0900
Subject: [PATCH v1 3/4] Reuse partition pruning results in parallel workers
Pass the leader's initial partition pruning results and unpruned
relids to parallel workers and reuse them via ExecutorPrep(). This
avoids repeating pruning logic in workers, which is not only
redundant but also risks divergence due to nondeterminism in pruning
steps or parameter evaluation timing.
Introduce ExecCheckInitialPruningResults() to verify that the results
match what the worker would compute. This check helps catch
inconsistencies across leader and worker pruning logic.
While valuable on its own, this change also lays the foundation for
future optimizations where the leader may take locks only on
surviving partitions. Ensuring that workers follow identical pruning
decisions makes such selective locking safe.
---
src/backend/executor/execParallel.c | 67 +++++++++++++++++++++++++++-
src/backend/executor/execPartition.c | 35 +++++++++++++++
src/include/executor/execPartition.h | 1 +
3 files changed, 102 insertions(+), 1 deletion(-)
diff --git a/src/backend/executor/execParallel.c b/src/backend/executor/execParallel.c
index aedbd9566d6..f16ef184c68 100644
--- a/src/backend/executor/execParallel.c
+++ b/src/backend/executor/execParallel.c
@@ -24,6 +24,7 @@
#include "postgres.h"
#include "executor/execParallel.h"
+#include "executor/execPartition.h"
#include "executor/executor.h"
#include "executor/nodeAgg.h"
#include "executor/nodeAppend.h"
@@ -65,6 +66,8 @@
#define PARALLEL_KEY_QUERY_TEXT UINT64CONST(0xE000000000000008)
#define PARALLEL_KEY_JIT_INSTRUMENTATION UINT64CONST(0xE000000000000009)
#define PARALLEL_KEY_WAL_USAGE UINT64CONST(0xE00000000000000A)
+#define PARALLEL_KEY_PARTITION_PRUNE_RESULTS UINT64CONST(0xE00000000000000B)
+#define PARALLEL_KEY_UNPRUNED_RELIDS UINT64CONST(0xE00000000000000C)
#define PARALLEL_TUPLE_QUEUE_SIZE 65536
@@ -608,12 +611,18 @@ ExecInitParallelPlan(PlanState *planstate, EState *estate,
FixedParallelExecutorState *fpes;
char *pstmt_data;
char *pstmt_space;
+ char *part_prune_results_data;
+ char *part_prune_results_space;
+ char *unpruned_relids_data;
+ char *unpruned_relids_space;
char *paramlistinfo_space;
BufferUsage *bufusage_space;
WalUsage *walusage_space;
SharedExecutorInstrumentation *instrumentation = NULL;
SharedJitInstrumentation *jit_instrumentation = NULL;
int pstmt_len;
+ int part_prune_results_len;
+ int unpruned_relids_len;
int paramlistinfo_len;
int instrumentation_len = 0;
int jit_instrumentation_len = 0;
@@ -642,6 +651,8 @@ ExecInitParallelPlan(PlanState *planstate, EState *estate,
/* Fix up and serialize plan to be sent to workers. */
pstmt_data = ExecSerializePlan(planstate->plan, estate);
+ part_prune_results_data = nodeToString(estate->es_part_prune_results);
+ unpruned_relids_data = nodeToString(estate->es_unpruned_relids);
/* Create a parallel context. */
pcxt = CreateParallelContext("postgres", "ParallelQueryMain", nworkers);
@@ -668,6 +679,16 @@ ExecInitParallelPlan(PlanState *planstate, EState *estate,
shm_toc_estimate_chunk(&pcxt->estimator, pstmt_len);
shm_toc_estimate_keys(&pcxt->estimator, 1);
+ /* Estimate space for serialized part_prune_results. */
+ part_prune_results_len = strlen(part_prune_results_data) + 1;
+ shm_toc_estimate_chunk(&pcxt->estimator, part_prune_results_len);
+ shm_toc_estimate_keys(&pcxt->estimator, 1);
+
+ /* Estimate space for serialized unpruned_relids. */
+ unpruned_relids_len = strlen(unpruned_relids_data) + 1;
+ shm_toc_estimate_chunk(&pcxt->estimator, unpruned_relids_len);
+ shm_toc_estimate_keys(&pcxt->estimator, 1);
+
/* Estimate space for serialized ParamListInfo. */
paramlistinfo_len = EstimateParamListSpace(estate->es_param_list_info);
shm_toc_estimate_chunk(&pcxt->estimator, paramlistinfo_len);
@@ -769,6 +790,16 @@ ExecInitParallelPlan(PlanState *planstate, EState *estate,
memcpy(pstmt_space, pstmt_data, pstmt_len);
shm_toc_insert(pcxt->toc, PARALLEL_KEY_PLANNEDSTMT, pstmt_space);
+ /* Store serialized part_prune_results */
+ part_prune_results_space = shm_toc_allocate(pcxt->toc, part_prune_results_len);
+ memcpy(part_prune_results_space, part_prune_results_data, part_prune_results_len);
+ shm_toc_insert(pcxt->toc, PARALLEL_KEY_PARTITION_PRUNE_RESULTS, part_prune_results_space);
+
+ /* Store serialized unpruned_relids */
+ unpruned_relids_space = shm_toc_allocate(pcxt->toc, unpruned_relids_len);
+ memcpy(unpruned_relids_space, unpruned_relids_data, unpruned_relids_len);
+ shm_toc_insert(pcxt->toc, PARALLEL_KEY_UNPRUNED_RELIDS, unpruned_relids_space);
+
/* Store serialized ParamListInfo. */
paramlistinfo_space = shm_toc_allocate(pcxt->toc, paramlistinfo_len);
shm_toc_insert(pcxt->toc, PARALLEL_KEY_PARAMLISTINFO, paramlistinfo_space);
@@ -1263,10 +1294,15 @@ ExecParallelGetQueryDesc(shm_toc *toc, DestReceiver *receiver,
int instrument_options)
{
char *pstmtspace;
+ char *part_prune_results_space;
+ char *unpruned_relids_space;
char *paramspace;
PlannedStmt *pstmt;
+ List *part_prune_results;
+ Bitmapset *unpruned_relids;
ParamListInfo paramLI;
char *queryString;
+ ExecPrep *prep = NULL;
/* Get the query string from shared memory */
queryString = shm_toc_lookup(toc, PARALLEL_KEY_QUERY_TEXT, false);
@@ -1279,9 +1315,38 @@ ExecParallelGetQueryDesc(shm_toc *toc, DestReceiver *receiver,
paramspace = shm_toc_lookup(toc, PARALLEL_KEY_PARAMLISTINFO, false);
paramLI = RestoreParamList(¶mspace);
+ /* Reconstruct leader-supplied part_prune_results and unpruned_relids. */
+ part_prune_results_space =
+ shm_toc_lookup(toc, PARALLEL_KEY_PARTITION_PRUNE_RESULTS, false);
+ part_prune_results = (List *) stringToNode(part_prune_results_space);
+ unpruned_relids_space =
+ shm_toc_lookup(toc, PARALLEL_KEY_UNPRUNED_RELIDS, false);
+ unpruned_relids = (Bitmapset *) stringToNode(unpruned_relids_space);
+
+ /*
+ * If pruning was done in the leader, build a prep estate in the worker
+ * and inject the leader's pruning results into it for reuse.
+ */
+ if (pstmt->partPruneInfos)
+ {
+ prep = ExecutorPrep(pstmt, paramLI, CurrentResourceOwner, false);
+ Assert(prep->prep_estate);
+
+ prep->prep_estate->es_part_prune_results = part_prune_results;
+ prep->prep_estate->es_unpruned_relids =
+ bms_add_members(prep->prep_estate->es_unpruned_relids,
+ unpruned_relids);
+
+ /*
+ * Verify that the pruning results passed from the leader match
+ * what the worker would independently compute.
+ */
+ ExecCheckInitialPruningResults(prep->prep_estate);
+ }
+
/* Create a QueryDesc for the query. */
return CreateQueryDesc(pstmt,
- NULL,
+ prep,
queryString,
GetActiveSnapshot(), InvalidSnapshot,
receiver, paramLI, NULL, instrument_options);
diff --git a/src/backend/executor/execPartition.c b/src/backend/executor/execPartition.c
index 187a480e508..3b450e3373f 100644
--- a/src/backend/executor/execPartition.c
+++ b/src/backend/executor/execPartition.c
@@ -1872,6 +1872,41 @@ ExecDoInitialPruning(EState *estate)
}
}
+/*
+ * ExecCheckInitialPruningResults
+ * Verify partition pruning results passed from the leader process.
+ *
+ * This is intended to be called during parallel worker query setup.
+ * It recomputes initial pruning results locally and compares them with
+ * those received from the leader. Any mismatch may indicate a divergence
+ * between leader and worker logic or environment.
+ */
+void
+ExecCheckInitialPruningResults(EState *estate)
+{
+ ListCell *lc;
+ int i;
+
+ Assert(estate->es_part_prune_results != NULL);
+ i = 0;
+ foreach(lc, estate->es_part_prune_states)
+ {
+ PartitionPruneState *prunestate = (PartitionPruneState *) lfirst(lc);
+ Bitmapset *reuse_validsubplans =
+ list_nth_node(Bitmapset, estate->es_part_prune_results, i);
+ Bitmapset *validsubplans = NULL;
+ Bitmapset *validsubplan_rtis = NULL;
+
+ if (prunestate->do_initial_prune)
+ validsubplans = ExecFindMatchingSubPlans(prunestate, true,
+ &validsubplan_rtis);
+ if (bms_nonempty_difference(validsubplans, reuse_validsubplans))
+ elog(ERROR, "different validsubplns in parallel worker");
+ if (bms_nonempty_difference(validsubplan_rtis, estate->es_unpruned_relids))
+ elog(ERROR, "different unprunable_relids in parallel worker");
+ }
+}
+
/*
* ExecInitPartitionExecPruning
* Initialize the data structures needed for runtime "exec" partition
diff --git a/src/include/executor/execPartition.h b/src/include/executor/execPartition.h
index ba8cc594fc9..126efd008e5 100644
--- a/src/include/executor/execPartition.h
+++ b/src/include/executor/execPartition.h
@@ -132,6 +132,7 @@ typedef struct PartitionPruneState
extern void ExecCreatePartitionPruneStates(EState *estate);
extern void ExecDoInitialPruning(EState *estate);
+extern void ExecCheckInitialPruningResults(EState *estate);
extern PartitionPruneState *ExecInitPartitionExecPruning(PlanState *planstate,
int n_total_subplans,
int part_prune_index,
--
2.47.3
[application/octet-stream] v1-0001-Refactor-partition-pruning-initialization-for-cla.patch (7.7K, 3-v1-0001-Refactor-partition-pruning-initialization-for-cla.patch)
download | inline diff:
From 243d407de86b0a73b9bd8c8dbc541f630eb33747 Mon Sep 17 00:00:00 2001
From: Amit Langote <[email protected]>
Date: Tue, 11 Nov 2025 21:18:24 +0900
Subject: [PATCH v1 1/4] Refactor partition pruning initialization for clarity
and modularity
Move the creation of PartitionPruneState structures out of
ExecDoInitialPruning() into a new ExecCreatePartitionPruneStates()
function. This separates the setup of pruning state from the execution
of initial pruning logic, making the code clearer and easier to
maintain.
Also simplify handling of unpruned relids by moving responsibility
for recording them in EState into CreatePartitionPruneState(),
avoiding the need to pass all_leafpart_rtis as an out parameter.
This refactoring allows callers to reuse the pruning setup logic
without always triggering pruning, a capability useful for future use
cases that may only need metadata initialization.
---
src/backend/executor/execPartition.c | 70 +++++++++++++++++-----------
src/include/executor/execPartition.h | 1 +
2 files changed, 43 insertions(+), 28 deletions(-)
diff --git a/src/backend/executor/execPartition.c b/src/backend/executor/execPartition.c
index aa12e9ad2ea..88b150c8d77 100644
--- a/src/backend/executor/execPartition.c
+++ b/src/backend/executor/execPartition.c
@@ -182,8 +182,7 @@ static char *ExecBuildSlotPartitionKeyDescription(Relation rel,
static List *adjust_partition_colnos(List *colnos, ResultRelInfo *leaf_part_rri);
static List *adjust_partition_colnos_using_map(List *colnos, AttrMap *attrMap);
static PartitionPruneState *CreatePartitionPruneState(EState *estate,
- PartitionPruneInfo *pruneinfo,
- Bitmapset **all_leafpart_rtis);
+ PartitionPruneInfo *pruneinfo);
static void InitPartitionPruneContext(PartitionPruneContext *context,
List *pruning_steps,
PartitionDesc partdesc,
@@ -1772,6 +1771,9 @@ adjust_partition_colnos_using_map(List *colnos, AttrMap *attrMap)
*
* Functions:
*
+ * ExecCreatePartitionPruneStates
+ * Create PartitionPruneState for all PartitionPruneInfos in the EState
+ *
* ExecDoInitialPruning:
* Perform runtime "initial" pruning, if necessary, to determine the set
* of child subnodes that need to be initialized during ExecInitNode() for
@@ -1796,6 +1798,29 @@ adjust_partition_colnos_using_map(List *colnos, AttrMap *attrMap)
*-------------------------------------------------------------------------
*/
+/*
+ * ExecCreatePartitionPruneStates
+ *
+ * Create a PartitionPruneState for each PartitionPruneInfo in the estate,
+ * and save them in estate->es_part_prune_states. This setup is required
+ * before any initial or runtime pruning can occur.
+ */
+void
+ExecCreatePartitionPruneStates(EState *estate)
+{
+ ListCell *lc;
+
+ foreach(lc, estate->es_part_prune_infos)
+ {
+ PartitionPruneInfo *pruneinfo = lfirst_node(PartitionPruneInfo, lc);
+ PartitionPruneState *prunestate;
+
+ /* Create and save the PartitionPruneState. */
+ prunestate = CreatePartitionPruneState(estate, pruneinfo);
+ estate->es_part_prune_states = lappend(estate->es_part_prune_states,
+ prunestate);
+ }
+}
/*
* ExecDoInitialPruning
@@ -1803,11 +1828,11 @@ adjust_partition_colnos_using_map(List *colnos, AttrMap *attrMap)
* of child subnodes that need to be initialized during ExecInitNode() for
* plan nodes that support partition pruning.
*
- * This function iterates over each PartitionPruneInfo entry in
- * estate->es_part_prune_infos. For each entry, it creates a PartitionPruneState
- * and adds it to es_part_prune_states. ExecInitPartitionExecPruning() accesses
+ * This function iterates over each PartitionPruneState in
+ * estate->es_part_prune_states, which must have been populated earlier by
+ * ExecCreatePartitionPruneStates(). ExecInitPartitionExecPruning() accesses
* these states through their corresponding indexes in es_part_prune_states and
- * assign each state to the parent node's PlanState, from where it will be used
+ * assigns each state to the parent node's PlanState, from where it will be used
* for "exec" pruning.
*
* If initial pruning steps exist for a PartitionPruneInfo entry, this function
@@ -1825,20 +1850,13 @@ ExecDoInitialPruning(EState *estate)
{
ListCell *lc;
- foreach(lc, estate->es_part_prune_infos)
+ Assert(estate->es_part_prune_results == NULL);
+ foreach(lc, estate->es_part_prune_states)
{
- PartitionPruneInfo *pruneinfo = lfirst_node(PartitionPruneInfo, lc);
- PartitionPruneState *prunestate;
+ PartitionPruneState *prunestate = (PartitionPruneState *) lfirst(lc);
Bitmapset *validsubplans = NULL;
- Bitmapset *all_leafpart_rtis = NULL;
Bitmapset *validsubplan_rtis = NULL;
- /* Create and save the PartitionPruneState. */
- prunestate = CreatePartitionPruneState(estate, pruneinfo,
- &all_leafpart_rtis);
- estate->es_part_prune_states = lappend(estate->es_part_prune_states,
- prunestate);
-
/*
* Perform initial pruning steps, if any, and save the result
* bitmapset or NULL as described in the header comment.
@@ -1846,8 +1864,6 @@ ExecDoInitialPruning(EState *estate)
if (prunestate->do_initial_prune)
validsubplans = ExecFindMatchingSubPlans(prunestate, true,
&validsubplan_rtis);
- else
- validsubplan_rtis = all_leafpart_rtis;
estate->es_unpruned_relids = bms_add_members(estate->es_unpruned_relids,
validsubplan_rtis);
@@ -1965,14 +1981,12 @@ ExecInitPartitionExecPruning(PlanState *planstate,
* parent plan node's PlanState.
*
* If initial pruning steps are to be skipped (e.g., during EXPLAIN
- * (GENERIC_PLAN)), *all_leafpart_rtis will be populated with the RT indexes of
- * all leaf partitions whose scanning subnode is included in the parent plan
- * node's list of child plans. The caller must add these RT indexes to
- * estate->es_unpruned_relids.
+ * (GENERIC_PLAN)), the RT indexes of all leaf partitions whose scanning
+ * subnode is included in the parent plan node's list of child plans are
+ * added to estate->es_unpruned_relids.
*/
static PartitionPruneState *
-CreatePartitionPruneState(EState *estate, PartitionPruneInfo *pruneinfo,
- Bitmapset **all_leafpart_rtis)
+CreatePartitionPruneState(EState *estate, PartitionPruneInfo *pruneinfo)
{
PartitionPruneState *prunestate;
int n_part_hierarchies;
@@ -2206,8 +2220,8 @@ CreatePartitionPruneState(EState *estate, PartitionPruneInfo *pruneinfo,
pinfo->execparamids);
/*
- * Return all leaf partition indexes if we're skipping pruning in
- * the EXPLAIN (GENERIC_PLAN) case.
+ * Add all leaf partition indexes to es_unpruned_relids if we're
+ * skipping pruning in the EXPLAIN (GENERIC_PLAN) case.
*/
if (pinfo->initial_pruning_steps && !prunestate->do_initial_prune)
{
@@ -2219,8 +2233,8 @@ CreatePartitionPruneState(EState *estate, PartitionPruneInfo *pruneinfo,
Index rtindex = pprune->leafpart_rti_map[part_index];
if (rtindex)
- *all_leafpart_rtis = bms_add_member(*all_leafpart_rtis,
- rtindex);
+ estate->es_unpruned_relids =
+ bms_add_member(estate->es_unpruned_relids, rtindex);
}
}
diff --git a/src/include/executor/execPartition.h b/src/include/executor/execPartition.h
index 3b3f46aced0..ba8cc594fc9 100644
--- a/src/include/executor/execPartition.h
+++ b/src/include/executor/execPartition.h
@@ -130,6 +130,7 @@ typedef struct PartitionPruneState
PartitionPruningData *partprunedata[FLEXIBLE_ARRAY_MEMBER];
} PartitionPruneState;
+extern void ExecCreatePartitionPruneStates(EState *estate);
extern void ExecDoInitialPruning(EState *estate);
extern PartitionPruneState *ExecInitPartitionExecPruning(PlanState *planstate,
int n_total_subplans,
--
2.47.3
[application/octet-stream] v1-0004-Use-pruning-aware-locking-in-cached-plans.patch (25.0K, 4-v1-0004-Use-pruning-aware-locking-in-cached-plans.patch)
download | inline diff:
From ddffccd68513bb0e68d6cf75810cf64cf9a4d757 Mon Sep 17 00:00:00 2001
From: Amit Langote <[email protected]>
Date: Tue, 11 Nov 2025 22:30:52 +0900
Subject: [PATCH v1 4/4] Use pruning-aware locking in cached plans
Extend GetCachedPlan() to perform ExecutorPrep() on each planned
statement, capturing unpruned relids and initial pruning results.
Use this data to acquire execution locks only on surviving partitions,
avoiding unnecessary locking of pruned tables even when using cached
plans.
Introduce CachedPlanPrepData to carry ExecutorPrep results
through the plan caching layer. Adjust call sites in SPI,
functions, portals, and EXPLAIN to propagate this data.
This ensures pruning decisions made during initial pruning are
consistently reused without redoing pruning logic in executor paths
like parallel workers. It also lays the groundwork for
pruning-dependent lock behavior during plan reuse.
To maintain correctness when all target partitions are pruned, also
reinstate the firstResultRel locking behavior lost in commit
28317de72. That commit required the first ModifyTable target to
remain initialized for executor assumptions to hold. We now
explicitly track these relids in PlannerGlobal and PlannedStmt so they
are locked even if pruned, preserving that rule across cached plan
reuse.
---
src/backend/commands/prepare.c | 15 +-
src/backend/executor/functions.c | 14 +-
src/backend/executor/nodeModifyTable.c | 4 +-
src/backend/executor/spi.c | 22 ++-
src/backend/optimizer/plan/planner.c | 1 +
src/backend/optimizer/plan/setrefs.c | 3 +
src/backend/tcop/postgres.c | 7 +-
src/backend/utils/cache/plancache.c | 223 ++++++++++++++++++++++++-
src/include/nodes/pathnodes.h | 3 +
src/include/nodes/plannodes.h | 7 +
src/include/utils/plancache.h | 23 ++-
11 files changed, 299 insertions(+), 23 deletions(-)
diff --git a/src/backend/commands/prepare.c b/src/backend/commands/prepare.c
index afd449c73ba..10fdff403b9 100644
--- a/src/backend/commands/prepare.c
+++ b/src/backend/commands/prepare.c
@@ -154,6 +154,7 @@ ExecuteQuery(ParseState *pstate,
{
PreparedStatement *entry;
CachedPlan *cplan;
+ CachedPlanPrepData cprep = {0};
List *plan_list;
ParamListInfo paramLI = NULL;
EState *estate = NULL;
@@ -193,7 +194,9 @@ ExecuteQuery(ParseState *pstate,
entry->plansource->query_string);
/* Replan if needed, and increment plan refcount for portal */
- cplan = GetCachedPlan(entry->plansource, paramLI, NULL, NULL);
+ cprep.context = portal->portalContext;
+ cprep.owner = portal->resowner;
+ cplan = GetCachedPlan(entry->plansource, paramLI, NULL, NULL, &cprep);
plan_list = cplan->stmt_list;
/*
@@ -205,7 +208,7 @@ ExecuteQuery(ParseState *pstate,
query_string,
entry->plansource->commandTag,
plan_list,
- NIL,
+ cprep.prep_list,
cplan);
/*
@@ -575,6 +578,7 @@ ExplainExecuteQuery(ExecuteStmt *execstmt, IntoClause *into, ExplainState *es,
PreparedStatement *entry;
const char *query_string;
CachedPlan *cplan;
+ CachedPlanPrepData cprep = {0};
List *plan_list;
List *prep_list;
ListCell *p;
@@ -633,8 +637,11 @@ ExplainExecuteQuery(ExecuteStmt *execstmt, IntoClause *into, ExplainState *es,
}
/* Replan if needed, and acquire a transient refcount */
+ cprep.context = CurrentMemoryContext;
+ cprep.owner = CurrentResourceOwner;
cplan = GetCachedPlan(entry->plansource, paramLI,
- CurrentResourceOwner, pstate->p_queryEnv);
+ CurrentResourceOwner, pstate->p_queryEnv,
+ &cprep);
INSTR_TIME_SET_CURRENT(planduration);
INSTR_TIME_SUBTRACT(planduration, planstart);
@@ -653,7 +660,7 @@ ExplainExecuteQuery(ExecuteStmt *execstmt, IntoClause *into, ExplainState *es,
}
plan_list = cplan->stmt_list;
- prep_list = NIL;
+ prep_list = cprep.prep_list;
/* Explain each query */
i = 0;
diff --git a/src/backend/executor/functions.c b/src/backend/executor/functions.c
index 633310c5f5b..8fc22fbd283 100644
--- a/src/backend/executor/functions.c
+++ b/src/backend/executor/functions.c
@@ -72,6 +72,7 @@ typedef struct execution_state
bool setsResult; /* true if this query produces func's result */
bool lazyEval; /* true if should fetch one row at a time */
PlannedStmt *stmt; /* plan for this query */
+ ExecPrep *prep; /* ExecutorPrep() output for this plan */
QueryDesc *qd; /* null unless status == RUN */
} execution_state;
@@ -657,6 +658,8 @@ init_execution_state(SQLFunctionCachePtr fcache)
execution_state *lasttages = NULL;
int nstmts;
ListCell *lc;
+ CachedPlanPrepData cprep = {0};
+ int i;
/*
* Clean up after previous query, if there was one.
@@ -695,10 +698,13 @@ init_execution_state(SQLFunctionCachePtr fcache)
* CurrentResourceOwner will be the same when ShutdownSQLFunction runs.)
*/
fcache->cowner = CurrentResourceOwner;
+ cprep.context = fcache->fcontext;
+ cprep.owner = fcache->cowner;
fcache->cplan = GetCachedPlan(plansource,
fcache->paramLI,
fcache->cowner,
- NULL);
+ NULL,
+ &cprep);
/*
* If necessary, make esarray[] bigger to hold the needed state.
@@ -719,9 +725,12 @@ init_execution_state(SQLFunctionCachePtr fcache)
/*
* Build execution_state list to match the number of contained plans.
*/
+ i = 0;
foreach(lc, fcache->cplan->stmt_list)
{
PlannedStmt *stmt = lfirst_node(PlannedStmt, lc);
+ ExecPrep *prep = cprep.prep_list ? list_nth(cprep.prep_list, i) :
+ NULL;
execution_state *newes;
/*
@@ -763,6 +772,7 @@ init_execution_state(SQLFunctionCachePtr fcache)
newes->setsResult = false; /* might change below */
newes->lazyEval = false; /* might change below */
newes->stmt = stmt;
+ newes->prep = prep;
newes->qd = NULL;
if (stmt->canSetTag)
@@ -1362,7 +1372,7 @@ postquel_start(execution_state *es, SQLFunctionCachePtr fcache)
dest = None_Receiver;
es->qd = CreateQueryDesc(es->stmt,
- NULL,
+ es->prep,
fcache->func->src,
GetActiveSnapshot(),
InvalidSnapshot,
diff --git a/src/backend/executor/nodeModifyTable.c b/src/backend/executor/nodeModifyTable.c
index 4c5647ac38a..c5812612f8d 100644
--- a/src/backend/executor/nodeModifyTable.c
+++ b/src/backend/executor/nodeModifyTable.c
@@ -4648,8 +4648,8 @@ ExecInitModifyTable(ModifyTable *node, EState *estate, int eflags)
* as a reference for building the ResultRelInfo of the target partition.
* In either case, it doesn't matter which result relation is kept, so we
* just keep the first one, if all others have been pruned. See also,
- * ExecDoInitialPruning(), which ensures that this first result relation
- * has been locked.
+ * AcquireExecutorLocksUnpruned(), which ensures that this first result
+ * relation has been locked.
*/
i = 0;
foreach(l, node->resultRelations)
diff --git a/src/backend/executor/spi.c b/src/backend/executor/spi.c
index 7a3cb944d6f..72d52baff4b 100644
--- a/src/backend/executor/spi.c
+++ b/src/backend/executor/spi.c
@@ -1579,6 +1579,7 @@ SPI_cursor_open_internal(const char *name, SPIPlanPtr plan,
{
CachedPlanSource *plansource;
CachedPlan *cplan;
+ CachedPlanPrepData cprep = {0};
List *stmt_list;
char *query_string;
Snapshot snapshot;
@@ -1659,7 +1660,10 @@ SPI_cursor_open_internal(const char *name, SPIPlanPtr plan,
*/
/* Replan if needed, and increment plan refcount for portal */
- cplan = GetCachedPlan(plansource, paramLI, NULL, _SPI_current->queryEnv);
+ cprep.context = portal->portalContext;
+ cprep.owner = portal->resowner;
+ cplan = GetCachedPlan(plansource, paramLI, NULL, _SPI_current->queryEnv,
+ &cprep);
stmt_list = cplan->stmt_list;
if (!plan->saved)
@@ -1685,7 +1689,7 @@ SPI_cursor_open_internal(const char *name, SPIPlanPtr plan,
query_string,
plansource->commandTag,
stmt_list,
- NIL,
+ cprep.prep_list, /* XXX - need copy? */
cplan);
/*
@@ -2078,6 +2082,7 @@ SPI_plan_get_cached_plan(SPIPlanPtr plan)
{
CachedPlanSource *plansource;
CachedPlan *cplan;
+ CachedPlanPrepData cprep = {0};
SPICallbackArg spicallbackarg;
ErrorContextCallback spierrcontext;
@@ -2101,9 +2106,12 @@ SPI_plan_get_cached_plan(SPIPlanPtr plan)
error_context_stack = &spierrcontext;
/* Get the generic plan for the query */
+ cprep.context = CurrentMemoryContext;
+ cprep.owner = CurrentResourceOwner;
cplan = GetCachedPlan(plansource, NULL,
plan->saved ? CurrentResourceOwner : NULL,
- _SPI_current->queryEnv);
+ _SPI_current->queryEnv,
+ &cprep);
Assert(cplan == plansource->gplan);
/* Pop the error context stack */
@@ -2501,6 +2509,7 @@ _SPI_execute_plan(SPIPlanPtr plan, const SPIExecuteOptions *options,
CachedPlanSource *plansource = (CachedPlanSource *) lfirst(lc1);
List *stmt_list;
ListCell *lc2;
+ CachedPlanPrepData cprep = {0};
List *prep_list;
int i;
@@ -2577,11 +2586,14 @@ _SPI_execute_plan(SPIPlanPtr plan, const SPIExecuteOptions *options,
* Replan if needed, and increment plan refcount. If it's a saved
* plan, the refcount must be backed by the plan_owner.
*/
+ cprep.context = CurrentMemoryContext;
+ cprep.owner = CurrentResourceOwner;
cplan = GetCachedPlan(plansource, options->params,
- plan_owner, _SPI_current->queryEnv);
+ plan_owner, _SPI_current->queryEnv,
+ &cprep);
stmt_list = cplan->stmt_list;
- prep_list = NIL;
+ prep_list = cprep.prep_list;
/*
* If we weren't given a specific snapshot to use, and the statement
diff --git a/src/backend/optimizer/plan/planner.c b/src/backend/optimizer/plan/planner.c
index c4fd646b999..4c76e78c1da 100644
--- a/src/backend/optimizer/plan/planner.c
+++ b/src/backend/optimizer/plan/planner.c
@@ -608,6 +608,7 @@ standard_planner(Query *parse, const char *query_string, int cursorOptions,
glob->prunableRelids);
result->permInfos = glob->finalrteperminfos;
result->resultRelations = glob->resultRelations;
+ result->firstResultRels = glob->firstResultRels;
result->appendRelations = glob->appendRelations;
result->subplans = glob->subplans;
result->rewindPlanIDs = glob->rewindPlanIDs;
diff --git a/src/backend/optimizer/plan/setrefs.c b/src/backend/optimizer/plan/setrefs.c
index ccdc9bc264a..229b39060ae 100644
--- a/src/backend/optimizer/plan/setrefs.c
+++ b/src/backend/optimizer/plan/setrefs.c
@@ -1274,6 +1274,9 @@ set_plan_refs(PlannerInfo *root, Plan *plan, int rtoffset)
lappend_int(root->glob->resultRelations,
splan->rootRelation);
}
+ root->glob->firstResultRels =
+ lappend_int(root->glob->firstResultRels,
+ linitial_int(splan->resultRelations));
}
break;
case T_Append:
diff --git a/src/backend/tcop/postgres.c b/src/backend/tcop/postgres.c
index d3964a12a14..82972beee70 100644
--- a/src/backend/tcop/postgres.c
+++ b/src/backend/tcop/postgres.c
@@ -1639,6 +1639,7 @@ exec_bind_message(StringInfo input_message)
int16 *rformats = NULL;
CachedPlanSource *psrc;
CachedPlan *cplan;
+ CachedPlanPrepData cprep = {0};
Portal portal;
char *query_string;
char *saved_stmt_name;
@@ -2021,7 +2022,9 @@ exec_bind_message(StringInfo input_message)
* will be generated in MessageContext. The plan refcount will be
* assigned to the Portal, so it will be released at portal destruction.
*/
- cplan = GetCachedPlan(psrc, params, NULL, NULL);
+ cprep.context = portal->portalContext;
+ cprep.owner = portal->resowner;
+ cplan = GetCachedPlan(psrc, params, NULL, NULL, &cprep);
/*
* Now we can define the portal.
@@ -2034,7 +2037,7 @@ exec_bind_message(StringInfo input_message)
query_string,
psrc->commandTag,
cplan->stmt_list,
- NIL,
+ cprep.prep_list,
cplan);
/* Portal is defined, set the plan ID based on its contents. */
diff --git a/src/backend/utils/cache/plancache.c b/src/backend/utils/cache/plancache.c
index 6661d2c6b73..ebcf601fce7 100644
--- a/src/backend/utils/cache/plancache.c
+++ b/src/backend/utils/cache/plancache.c
@@ -93,7 +93,7 @@ static bool StmtPlanRequiresRevalidation(CachedPlanSource *plansource);
static bool BuildingPlanRequiresSnapshot(CachedPlanSource *plansource);
static List *RevalidateCachedQuery(CachedPlanSource *plansource,
QueryEnvironment *queryEnv);
-static bool CheckCachedPlan(CachedPlanSource *plansource);
+static bool PrepAndCheckCachedPlan(CachedPlanSource *plansource, CachedPlanPrepData *cprep);
static CachedPlan *BuildCachedPlan(CachedPlanSource *plansource, List *qlist,
ParamListInfo boundParams, QueryEnvironment *queryEnv);
static bool choose_custom_plan(CachedPlanSource *plansource,
@@ -101,6 +101,8 @@ static bool choose_custom_plan(CachedPlanSource *plansource,
static double cached_plan_cost(CachedPlan *plan, bool include_planner);
static Query *QueryListGetPrimaryStmt(List *stmts);
static void AcquireExecutorLocks(List *stmt_list, bool acquire);
+static void AcquireExecutorLocksUnpruned(List *stmt_list, bool acquire,
+ CachedPlanPrepData *cprep);
static void AcquirePlannerLocks(List *stmt_list, bool acquire);
static void ScanQueryForLocks(Query *parsetree, bool acquire);
static bool ScanQueryWalker(Node *node, bool *acquire);
@@ -137,6 +139,26 @@ ResourceOwnerForgetPlanCacheRef(ResourceOwner owner, CachedPlan *plan)
/* GUC parameter */
int plan_cache_mode = PLAN_CACHE_MODE_AUTO;
+/*
+ * Lock acquisition policy for execution locks.
+ *
+ * LOCK_ALL acquires locks on all relations mentioned in the plan,
+ * reproducing the behavior of AcquireExecutorLocks().
+ *
+ * LOCK_UNPRUNED restricts locking to only the unpruned relations. That
+ * includes those mentioned in PlannedStmt.unprunableRelids and the leaf
+ * partitions remaining after performing initial pruning.
+ */
+typedef enum LockPolicy
+{
+ LOCK_ALL,
+ LOCK_UNPRUNED,
+} LockPolicy;
+
+static void AcquireExecutorLocksWithPolicy(List *stmt_list,
+ LockPolicy policy, bool acquire,
+ CachedPlanPrepData *cprep);
+
/*
* InitPlanCache: initialize module during InitPostgres.
*
@@ -938,7 +960,12 @@ RevalidateCachedQuery(CachedPlanSource *plansource,
}
/*
- * CheckCachedPlan: see if the CachedPlanSource's generic plan is valid.
+ * PrepAndCheckCachedPlan: see if the CachedPlanSource's generic plan is valid.
+ *
+ * If 'cprep' is not NULL, ExecutorPrep() is applied to each PlannedStmt to
+ * compute the set of partitions that survive initial runtime pruning in order
+ * to only lock them. The resulting ExecPrep structures are saved in cprep for
+ * later reuse by ExecutorStart().
*
* Caller must have already called RevalidateCachedQuery to verify that the
* querytree is up to date.
@@ -947,7 +974,7 @@ RevalidateCachedQuery(CachedPlanSource *plansource,
* (We must do this for the "true" result to be race-condition-free.)
*/
static bool
-CheckCachedPlan(CachedPlanSource *plansource)
+PrepAndCheckCachedPlan(CachedPlanSource *plansource, CachedPlanPrepData *cprep)
{
CachedPlan *plan = plansource->gplan;
@@ -975,13 +1002,15 @@ CheckCachedPlan(CachedPlanSource *plansource)
*/
if (plan->is_valid)
{
+ LockPolicy policy = !cprep ? LOCK_ALL : LOCK_UNPRUNED;
+
/*
* Plan must have positive refcount because it is referenced by
* plansource; so no need to fear it disappears under us here.
*/
Assert(plan->refcount > 0);
- AcquireExecutorLocks(plan->stmt_list, true);
+ AcquireExecutorLocksWithPolicy(plan->stmt_list, policy, true, cprep);
/*
* If plan was transient, check to see if TransactionXmin has
@@ -1003,7 +1032,7 @@ CheckCachedPlan(CachedPlanSource *plansource)
}
/* Oops, the race case happened. Release useless locks. */
- AcquireExecutorLocks(plan->stmt_list, false);
+ AcquireExecutorLocksWithPolicy(plan->stmt_list, policy, false, cprep);
}
/*
@@ -1283,6 +1312,10 @@ cached_plan_cost(CachedPlan *plan, bool include_planner)
* On return, the plan is valid and we have sufficient locks to begin
* execution.
*
+ * If 'cprep' is not NULL and a generic plan is reused, the function prepares
+ * each PlannedStmt via ExecutorPrep() and stores the results in
+ * cprep->prep_list. These are intended to be passed later to ExecutorStart().
+ *
* On return, the refcount of the plan has been incremented; a later
* ReleaseCachedPlan() call is expected. If "owner" is not NULL then
* the refcount has been reported to that ResourceOwner (note that this
@@ -1293,7 +1326,8 @@ cached_plan_cost(CachedPlan *plan, bool include_planner)
*/
CachedPlan *
GetCachedPlan(CachedPlanSource *plansource, ParamListInfo boundParams,
- ResourceOwner owner, QueryEnvironment *queryEnv)
+ ResourceOwner owner, QueryEnvironment *queryEnv,
+ CachedPlanPrepData *cprep)
{
CachedPlan *plan = NULL;
List *qlist;
@@ -1315,7 +1349,9 @@ GetCachedPlan(CachedPlanSource *plansource, ParamListInfo boundParams,
if (!customplan)
{
- if (CheckCachedPlan(plansource))
+ if (cprep)
+ cprep->params = boundParams;
+ if (PrepAndCheckCachedPlan(plansource, cprep))
{
/* We want a generic plan, and we already have a valid one */
plan = plansource->gplan;
@@ -1902,6 +1938,32 @@ QueryListGetPrimaryStmt(List *stmts)
return NULL;
}
+/*
+ * AcquireExecutorLocksWithPolicy
+ * Acquire or release execution locks for a plan according to
+ * the specified policy.
+ *
+ * The policy determines whether all relations or only unpruned ones are locked.
+ * For LOCK_UNPRUNED, ExecutorPrep is invoked to identify surviving partitions
+ * and its result is populated in cprep.
+ */
+static void
+AcquireExecutorLocksWithPolicy(List *stmt_list, LockPolicy policy, bool acquire,
+ CachedPlanPrepData *cprep)
+{
+ switch (policy)
+ {
+ case LOCK_ALL:
+ AcquireExecutorLocks(stmt_list, acquire);
+ break;
+ case LOCK_UNPRUNED:
+ AcquireExecutorLocksUnpruned(stmt_list, acquire, cprep);
+ break;
+ default:
+ elog(ERROR, "invalid LockPolicy");
+ }
+}
+
/*
* AcquireExecutorLocks: acquire locks needed for execution of a cached plan;
* or release them if acquire is false.
@@ -1954,6 +2016,153 @@ AcquireExecutorLocks(List *stmt_list, bool acquire)
}
}
+/*
+ * LockRelids
+ * Acquire or release locks on the specified relids, which reference
+ * entries in the provided range table.
+ *
+ * Helper for AcquireExecutorLocksUnpruned().
+ */
+static void
+LockRelids(List *rtable, Bitmapset *relids, bool acquire)
+{
+ int rtindex = -1;
+
+ while ((rtindex = bms_next_member(relids, rtindex)) >= 0)
+ {
+ RangeTblEntry *rte = list_nth_node(RangeTblEntry, rtable, rtindex - 1);
+
+ Assert(rte->rtekind == RTE_RELATION ||
+ (rte->rtekind == RTE_SUBQUERY && OidIsValid(rte->relid)));
+
+ /*
+ * Acquire the appropriate type of lock on each relation OID. Note
+ * that we don't actually try to open the rel, and hence will not
+ * fail if it's been dropped entirely --- we'll just transiently
+ * acquire a non-conflicting lock.
+ */
+ if (acquire)
+ LockRelationOid(rte->relid, rte->rellockmode);
+ else
+ UnlockRelationOid(rte->relid, rte->rellockmode);
+ }
+}
+
+/*
+ * AcquireExecutorLocksUnpruned
+ * Acquire or release execution locks for only unpruned relations
+ * referenced by the given PlannedStmts.
+ *
+ * This function uses ExecutorPrep to identify which partitions survive
+ * initial runtime pruning and locks only those, along with any unprunable
+ * base relations. During acquire, the resulting ExecPrep objects are stored
+ * in cprep->prep_list for later reuse. During release, those same ExecPrep
+ * objects are used to identify what to unlock.
+ *
+ * Unlike AcquireExecutorLocks(), which locks all relations listed in the
+ * PlannedStmt's rtable (LOCK_ALL policy), this function selectively locks
+ * only those rels that may be referenced during execution.
+ *
+ * prep_list is extended during acquire and must match stmt_list during
+ * release. Memory allocation happens in cprep->context.
+ */
+static void
+AcquireExecutorLocksUnpruned(List *stmt_list, bool acquire,
+ CachedPlanPrepData *cprep)
+{
+ MemoryContext oldcontext = MemoryContextSwitchTo(cprep->context);
+ ListCell *lc1;
+ List *prep_list;
+ int i;
+
+ Assert(cprep);
+
+ /*
+ * When releasing locks, use the ExecPrep list (if any) created during
+ * acquisition to determine which relids to unlock. The list must match
+ * the PlannedStmt list one-to-one.
+ */
+ prep_list = cprep->prep_list;
+ Assert(acquire || list_length(prep_list) == list_length(stmt_list));
+
+ i = 0;
+ foreach(lc1, stmt_list)
+ {
+ PlannedStmt *plannedstmt = lfirst_node(PlannedStmt, lc1);
+ ExecPrep *prep;
+
+ if (plannedstmt->commandType == CMD_UTILITY)
+ {
+ /* Same as AcquireExecutorLocks(). */
+ Query *query = UtilityContainsQuery(plannedstmt->utilityStmt);
+
+ if (query)
+ ScanQueryForLocks(query, acquire);
+
+ /* Keep the list one-to-one with stmt_list. */
+ if (acquire)
+ cprep->prep_list = lappend(cprep->prep_list, NULL);
+ continue;
+ }
+
+ /*
+ * Lock tables mentioned in the original query and other unprunable
+ * relations that were added to the plan via inheritance expansion.
+ */
+ LockRelids(plannedstmt->rtable, plannedstmt->unprunableRelids, acquire);
+
+ /* Lock partitions surviving runtime initial pruning. */
+ if (acquire)
+ {
+ prep = ExecutorPrep(plannedstmt, cprep->params, cprep->owner, true);
+ Assert(prep || plannedstmt->partPruneInfos == NULL);
+ cprep->prep_list = lappend(cprep->prep_list, prep);
+ }
+ else
+ prep = list_nth(prep_list, i++);
+
+ Assert(prep == NULL || prep->prep_estate);
+ if (prep)
+ {
+ EState *prep_estate = prep->prep_estate;
+
+ /*
+ * es_unpruned_relids includes plannedstmt->unprunableRelids,
+ * which we've already locked. Filter them out to avoid double-locking.
+ */
+ Bitmapset *lock_relids = bms_difference(prep_estate->es_unpruned_relids,
+ plannedstmt->unprunableRelids);
+
+ /*
+ * firstResultRels may contain pruned partitions that must still be
+ * locked to satisfy executor assumptions (see comments in
+ * ExecInitModifyTable(). Ensure they’re included here.
+ */
+ if (plannedstmt->resultRelations)
+ {
+ ListCell *lc2;
+
+ foreach(lc2, plannedstmt->firstResultRels)
+ {
+ Index firstResultRel = lfirst_int(lc2);
+
+ if (!bms_is_member(firstResultRel, lock_relids))
+ lock_relids = bms_add_member(lock_relids, firstResultRel);
+ }
+ }
+
+ LockRelids(plannedstmt->rtable, lock_relids, acquire);
+ bms_free(lock_relids);
+ }
+
+ /* Clean up prep if releasing locks. */
+ if (!acquire)
+ ExecPrepCleanup(prep);
+ }
+
+ MemoryContextSwitchTo(oldcontext);
+}
+
/*
* AcquirePlannerLocks: acquire locks needed for planning of a querytree list;
* or release them if acquire is false.
diff --git a/src/include/nodes/pathnodes.h b/src/include/nodes/pathnodes.h
index 30d889b54c5..6fb86dc05f6 100644
--- a/src/include/nodes/pathnodes.h
+++ b/src/include/nodes/pathnodes.h
@@ -141,6 +141,9 @@ typedef struct PlannerGlobal
/* "flat" list of integer RT indexes */
List *resultRelations;
+ /* "flat" list of integer RT indexes (one per ModifyTable node) */
+ List *firstResultRels;
+
/* "flat" list of AppendRelInfos */
List *appendRelations;
diff --git a/src/include/nodes/plannodes.h b/src/include/nodes/plannodes.h
index c4393a94321..42b51299ece 100644
--- a/src/include/nodes/plannodes.h
+++ b/src/include/nodes/plannodes.h
@@ -123,6 +123,13 @@ typedef struct PlannedStmt
/* integer list of RT indexes, or NIL */
List *resultRelations;
+ /*
+ * rtable indexes of first target relation in each ModifyTable node in the
+ * plan for INSERT/UPDATE/DELETE/MERGE
+ */
+ /* integer list of RT indexes, or NIL */
+ List *firstResultRels;
+
/* list of AppendRelInfo nodes */
List *appendRelations;
diff --git a/src/include/utils/plancache.h b/src/include/utils/plancache.h
index a82b66d4bc2..59f0b0fc4a4 100644
--- a/src/include/utils/plancache.h
+++ b/src/include/utils/plancache.h
@@ -197,6 +197,26 @@ typedef struct CachedExpression
} CachedExpression;
+/*
+ * CachedPlanPrepData
+ * Carries ExecutorPrep results for each PlannedStmt in a CachedPlan,
+ * along with context and owner information needed to allocate them.
+ *
+ * Populated by GetCachedPlan() when ExecutorPrep is run on a generic plan.
+ *
+ * prep_list: results from ExecutorPrep(), one per PlannedStmt
+ * params: parameters that may be used during ExecutorPrep (e.g., pruning)
+ * context: memory context to allocate ExecutorPrep results in
+ * owner: resource owner to associate ExecutorPrep resources with
+ */
+typedef struct CachedPlanPrepData
+{
+ List *prep_list; /* List of ExecPrep */
+ ParamListInfo params;
+ MemoryContext context;
+ ResourceOwner owner;
+} CachedPlanPrepData;
+
extern void InitPlanCache(void);
extern void ResetPlanCache(void);
@@ -240,7 +260,8 @@ extern List *CachedPlanGetTargetList(CachedPlanSource *plansource,
extern CachedPlan *GetCachedPlan(CachedPlanSource *plansource,
ParamListInfo boundParams,
ResourceOwner owner,
- QueryEnvironment *queryEnv);
+ QueryEnvironment *queryEnv,
+ CachedPlanPrepData *cprep);
extern void ReleaseCachedPlan(CachedPlan *plan, ResourceOwner owner);
extern bool CachedPlanAllowsSimpleValidityCheck(CachedPlanSource *plansource,
--
2.47.3
[application/octet-stream] v1-0002-Introduce-ExecutorPrep-infrastructure-for-pre-exe.patch (29.9K, 5-v1-0002-Introduce-ExecutorPrep-infrastructure-for-pre-exe.patch)
download | inline diff:
From e9689618f2889f224eb62e9ff4fb5251285ecdb3 Mon Sep 17 00:00:00 2001
From: Amit Langote <[email protected]>
Date: Tue, 11 Nov 2025 21:47:46 +0900
Subject: [PATCH v1 2/4] Introduce ExecutorPrep infrastructure for
pre-execution setup
Add ExecutorPrep() and ExecPrep to support setting up executor
metadata like range table initialization and partition pruning
ahead of actual execution. This enables execution paths to
perform setup independently of running the plan.
For example, plan validation can compute and consume this
metadata without executing the query. Parallel query workers
can receive pre-initialized state from the leader and pass it
to ExecutorStart, avoiding redundant setup.
ExecutorStart now accepts a prep-estate from QueryDesc to skip
repeating initialization. The ExecPrep wrapper manages cleanup
and signals ownership of the estate. PrepPlan() encapsulates
shared setup logic.
Call sites, including Portal, SPI, and EXPLAIN, are updated to
support passing down the prep data. These changes are mostly
mechanical and clarify the separation between setup and actual
execution.
---
src/backend/commands/copyto.c | 2 +-
src/backend/commands/createas.c | 2 +-
src/backend/commands/explain.c | 7 +-
src/backend/commands/extension.c | 1 +
src/backend/commands/matview.c | 2 +-
src/backend/commands/portalcmds.c | 1 +
src/backend/commands/prepare.c | 11 +-
src/backend/executor/README | 9 +-
src/backend/executor/execMain.c | 192 +++++++++++++++++++++++----
src/backend/executor/execParallel.c | 1 +
src/backend/executor/execPartition.c | 3 +
src/backend/executor/functions.c | 1 +
src/backend/executor/spi.c | 10 ++
src/backend/tcop/postgres.c | 2 +
src/backend/tcop/pquery.c | 27 +++-
src/backend/utils/mmgr/portalmem.c | 2 +
src/include/commands/explain.h | 3 +-
src/include/executor/execdesc.h | 3 +-
src/include/executor/executor.h | 10 ++
src/include/nodes/execnodes.h | 55 ++++++++
src/include/utils/portal.h | 2 +
21 files changed, 308 insertions(+), 38 deletions(-)
diff --git a/src/backend/commands/copyto.c b/src/backend/commands/copyto.c
index cef452584e5..5efbb0949c2 100644
--- a/src/backend/commands/copyto.c
+++ b/src/backend/commands/copyto.c
@@ -870,7 +870,7 @@ BeginCopyTo(ParseState *pstate,
((DR_copy *) dest)->cstate = cstate;
/* Create a QueryDesc requesting no output */
- cstate->queryDesc = CreateQueryDesc(plan, pstate->p_sourcetext,
+ cstate->queryDesc = CreateQueryDesc(plan, NULL, pstate->p_sourcetext,
GetActiveSnapshot(),
InvalidSnapshot,
dest, NULL, NULL, 0);
diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c
index 1ccc2e55c64..9eabe4920cd 100644
--- a/src/backend/commands/createas.c
+++ b/src/backend/commands/createas.c
@@ -334,7 +334,7 @@ ExecCreateTableAs(ParseState *pstate, CreateTableAsStmt *stmt,
UpdateActiveSnapshotCommandId();
/* Create a QueryDesc, redirecting output to our tuple receiver */
- queryDesc = CreateQueryDesc(plan, pstate->p_sourcetext,
+ queryDesc = CreateQueryDesc(plan, NULL, pstate->p_sourcetext,
GetActiveSnapshot(), InvalidSnapshot,
dest, params, queryEnv, 0);
diff --git a/src/backend/commands/explain.c b/src/backend/commands/explain.c
index 7e699f8595e..d6ab3697dd9 100644
--- a/src/backend/commands/explain.c
+++ b/src/backend/commands/explain.c
@@ -370,7 +370,7 @@ standard_ExplainOneQuery(Query *query, int cursorOptions,
}
/* run it (if needed) and produce output */
- ExplainOnePlan(plan, into, es, queryString, params, queryEnv,
+ ExplainOnePlan(plan, NULL, into, es, queryString, params, queryEnv,
&planduration, (es->buffers ? &bufusage : NULL),
es->memory ? &mem_counters : NULL);
}
@@ -492,7 +492,8 @@ ExplainOneUtility(Node *utilityStmt, IntoClause *into, ExplainState *es,
* to call it.
*/
void
-ExplainOnePlan(PlannedStmt *plannedstmt, IntoClause *into, ExplainState *es,
+ExplainOnePlan(PlannedStmt *plannedstmt, ExecPrep *prep,
+ IntoClause *into, ExplainState *es,
const char *queryString, ParamListInfo params,
QueryEnvironment *queryEnv, const instr_time *planduration,
const BufferUsage *bufusage,
@@ -548,7 +549,7 @@ ExplainOnePlan(PlannedStmt *plannedstmt, IntoClause *into, ExplainState *es,
dest = None_Receiver;
/* Create a QueryDesc for the query */
- queryDesc = CreateQueryDesc(plannedstmt, queryString,
+ queryDesc = CreateQueryDesc(plannedstmt, prep, queryString,
GetActiveSnapshot(), InvalidSnapshot,
dest, params, queryEnv, instrument_option);
diff --git a/src/backend/commands/extension.c b/src/backend/commands/extension.c
index 93ef1ad106f..3cca6d45ec1 100644
--- a/src/backend/commands/extension.c
+++ b/src/backend/commands/extension.c
@@ -993,6 +993,7 @@ execute_sql_string(const char *sql, const char *filename)
QueryDesc *qdesc;
qdesc = CreateQueryDesc(stmt,
+ NULL,
sql,
GetActiveSnapshot(), NULL,
dest, NULL, NULL, 0);
diff --git a/src/backend/commands/matview.c b/src/backend/commands/matview.c
index ef7c0d624f1..30cbf9f264f 100644
--- a/src/backend/commands/matview.c
+++ b/src/backend/commands/matview.c
@@ -437,7 +437,7 @@ refresh_matview_datafill(DestReceiver *dest, Query *query,
UpdateActiveSnapshotCommandId();
/* Create a QueryDesc, redirecting output to our tuple receiver */
- queryDesc = CreateQueryDesc(plan, queryString,
+ queryDesc = CreateQueryDesc(plan, NULL, queryString,
GetActiveSnapshot(), InvalidSnapshot,
dest, NULL, NULL, 0);
diff --git a/src/backend/commands/portalcmds.c b/src/backend/commands/portalcmds.c
index ec96c2efcd3..ac1ddd25aba 100644
--- a/src/backend/commands/portalcmds.c
+++ b/src/backend/commands/portalcmds.c
@@ -118,6 +118,7 @@ PerformCursorOpen(ParseState *pstate, DeclareCursorStmt *cstmt, ParamListInfo pa
queryString,
CMDTAG_SELECT, /* cursor's query is always a SELECT */
list_make1(plan),
+ list_make1(NULL),
NULL);
/*----------
diff --git a/src/backend/commands/prepare.c b/src/backend/commands/prepare.c
index 34b6410d6a2..afd449c73ba 100644
--- a/src/backend/commands/prepare.c
+++ b/src/backend/commands/prepare.c
@@ -205,6 +205,7 @@ ExecuteQuery(ParseState *pstate,
query_string,
entry->plansource->commandTag,
plan_list,
+ NIL,
cplan);
/*
@@ -575,6 +576,7 @@ ExplainExecuteQuery(ExecuteStmt *execstmt, IntoClause *into, ExplainState *es,
const char *query_string;
CachedPlan *cplan;
List *plan_list;
+ List *prep_list;
ListCell *p;
ParamListInfo paramLI = NULL;
EState *estate = NULL;
@@ -585,6 +587,7 @@ ExplainExecuteQuery(ExecuteStmt *execstmt, IntoClause *into, ExplainState *es,
MemoryContextCounters mem_counters;
MemoryContext planner_ctx = NULL;
MemoryContext saved_ctx = NULL;
+ int i;
if (es->memory)
{
@@ -650,14 +653,20 @@ ExplainExecuteQuery(ExecuteStmt *execstmt, IntoClause *into, ExplainState *es,
}
plan_list = cplan->stmt_list;
+ prep_list = NIL;
/* Explain each query */
+ i = 0;
foreach(p, plan_list)
{
PlannedStmt *pstmt = lfirst_node(PlannedStmt, p);
+ ExecPrep *prep = prep_list ?
+ (ExecPrep *) list_nth(prep_list, i) : NULL;
+ i++;
if (pstmt->commandType != CMD_UTILITY)
- ExplainOnePlan(pstmt, into, es, query_string, paramLI, pstate->p_queryEnv,
+ ExplainOnePlan(pstmt, prep,
+ into, es, query_string, paramLI, pstate->p_queryEnv,
&planduration, (es->buffers ? &bufusage : NULL),
es->memory ? &mem_counters : NULL);
else
diff --git a/src/backend/executor/README b/src/backend/executor/README
index 54f4782f31b..6e481398f18 100644
--- a/src/backend/executor/README
+++ b/src/backend/executor/README
@@ -291,10 +291,17 @@ Query Processing Control Flow
This is a sketch of control flow for full query processing:
+ [Optional] ExecutorPrep
+ - May be run before ExecutorStart (e.g., for plan validation).
+ - Performs range table initialization, permission checks, and
+ initial partition pruning.
+ - Returns an ExecPrep wrapper with EState that ExecutorStart may
+ reuse.
+
CreateQueryDesc
ExecutorStart
- CreateExecutorState
+ CreateExecutorState (or reuse one from ExecPrep if present)
creates per-query context
switch to per-query context to run ExecInitNode
AfterTriggerBeginQuery
diff --git a/src/backend/executor/execMain.c b/src/backend/executor/execMain.c
index 27c9eec697b..1b96b251c34 100644
--- a/src/backend/executor/execMain.c
+++ b/src/backend/executor/execMain.c
@@ -75,6 +75,7 @@ ExecutorCheckPerms_hook_type ExecutorCheckPerms_hook = NULL;
/* decls for local routines only used within this module */
static void InitPlan(QueryDesc *queryDesc, int eflags);
+static void PrepPlan(EState *estate, bool do_initial_pruning);
static void CheckValidRowMarkRel(Relation rel, RowMarkType markType);
static void ExecPostprocessPlan(EState *estate);
static void ExecEndPlan(PlanState *planstate, EState *estate);
@@ -171,8 +172,24 @@ standard_ExecutorStart(QueryDesc *queryDesc, int eflags)
/*
* Build EState, switch into per-query memory context for startup.
+ *
+ * If ExecutorPrep() ran earlier (e.g., to do initial pruning during plan
+ * validity checking), reuse its EState to avoid redoing range table setup
+ * and pruning. Otherwise, create a fresh EState as usual.
*/
- estate = CreateExecutorState();
+ if (queryDesc->prep)
+ {
+ estate = queryDesc->prep->prep_estate;
+
+ /*
+ * Executor is adopting the prep's EState. Mark it so ExecPrepCleanup()
+ * doesn't try to free it redundantly.
+ */
+ queryDesc->prep->owns_estate = false;
+ }
+ else
+ estate = CreateExecutorState();
+
queryDesc->estate = estate;
oldcontext = MemoryContextSwitchTo(estate->es_query_cxt);
@@ -263,6 +280,143 @@ standard_ExecutorStart(QueryDesc *queryDesc, int eflags)
MemoryContextSwitchTo(oldcontext);
}
+/*
+ * ExecutorPrep: prepare executor state for a PlannedStmt outside ExecutorStart.
+ *
+ * Performs range table initialization, permission checks, and initial
+ * partition pruning if partPruneInfos are present and do_initial_pruning is
+ * true.
+ *
+ * This is intended for callers that need executor metadata ahead of actual
+ * execution. Typical use cases include:
+ * - determining which relations must be locked during plan cache validation;
+ * - initializing unpruned relids and valid subplans in parallel workers
+ * using state copied from the leader.
+ *
+ * The executor can reuse the resulting state to avoid redundant setup during
+ * ExecutorStart(); see InitPlan().
+ *
+ * Returns an ExecPrep wrapper that owns the EState and can be reused
+ * or cleaned up later. Returns NULL if no prep is needed (e.g. no pruning).
+ */
+ExecPrep *
+ExecutorPrep(PlannedStmt *pstmt, ParamListInfo params, ResourceOwner owner,
+ bool do_initial_pruning)
+{
+ ResourceOwner oldowner;
+ EState *estate;
+
+ Assert(pstmt->commandType != CMD_UTILITY);
+
+ /* No pruning needed -- let normal ExecutorStart handle setup later. */
+ if (pstmt->partPruneInfos == NIL)
+ return NULL;
+
+ estate = CreateExecutorState();
+ estate->es_plannedstmt = pstmt;
+ estate->es_part_prune_infos = pstmt->partPruneInfos;
+ estate->es_param_list_info = params;
+
+ /*
+ * Ensure locks taken during initial pruning are tracked under the given
+ * ResourceOwner (e.g., one associated with CachedPlan validation).
+ */
+ oldowner = CurrentResourceOwner;
+ CurrentResourceOwner = owner;
+
+ PrepPlan(estate, do_initial_pruning);
+
+ CurrentResourceOwner = oldowner;
+
+ return CreateExecPrep(estate, CurrentMemoryContext, NULL, NULL);
+}
+
+/*
+ * PrepPlan: initialize executor metadata needed before plan execution.
+ *
+ * Sets up permissions, range table, and partition pruning infrastructure.
+ * If do_initial_pruning is true, performs initial pruning and stores the
+ * resulting subplan indexes in es_part_prune_results. Otherwise, this step
+ * is skipped, typically when results are provided externally (e.g., in
+ * parallel workers).
+ *
+ * Called from both ExecutorPrep() and InitPlan().
+ */
+static void
+PrepPlan(EState *estate, bool do_initial_pruning)
+{
+ PlannedStmt *pstmt = estate->es_plannedstmt;
+
+ /*
+ * Do permissions checks.
+ */
+ ExecCheckPermissions(pstmt->rtable, pstmt->permInfos, true);
+
+ /*
+ * Initialize range table.
+ */
+ ExecInitRangeTable(estate, pstmt->rtable, pstmt->permInfos,
+ bms_copy(pstmt->unprunableRelids));
+
+ /*
+ * Set up PartitionPruneState structures needed for both initial and
+ * runtime partition pruning. These structures are built from the
+ * PartitionPruneInfo entries in the plan tree.
+ *
+ * If do_initial_pruning is true, also perform initial pruning to compute
+ * the subset of child subplans that will be executed. The results,
+ * which are bitmapsets of selected child indexes, are saved in
+ * es_part_prune_results. This list is parallel to es_part_prune_infos.
+ *
+ * In parallel workers, do_initial_pruning should be false — they receive
+ * es_part_prune_results from the leader process and should only initialize
+ * the PartitionPruneStates.
+ */
+ ExecCreatePartitionPruneStates(estate);
+ if (do_initial_pruning)
+ ExecDoInitialPruning(estate);
+}
+
+/*
+ * CreateExecPrep: initialize ExecPrep wrapper with optional cleanup metadata.
+ */
+ExecPrep *
+CreateExecPrep(EState *estate, MemoryContext context,
+ execprep_cleanup_fn cleanup, void *cleanup_arg)
+{
+ ExecPrep *prep = palloc0(sizeof(ExecPrep));
+
+ prep->prep_estate = estate;
+ prep->context = context;
+ prep->cleanup = cleanup;
+ prep->cleanup_arg = cleanup_arg;
+ prep->owns_estate = true;
+
+ return prep;
+}
+
+/*
+ * ExecPrepCleanup: free ExecPrep resources not adopted by the executor.
+ *
+ * Only frees the EState if it wasn't taken over by ExecutorStart().
+ * Always runs the optional user-defined cleanup callback.
+ */
+void
+ExecPrepCleanup(ExecPrep *prep)
+{
+ if (prep == NULL)
+ return;
+
+ if (prep->prep_estate && prep->owns_estate)
+ {
+ ExecCloseRangeTableRelations(prep->prep_estate);
+ FreeExecutorState(prep->prep_estate);
+ }
+
+ if (prep->cleanup)
+ prep->cleanup(prep->cleanup_arg);
+}
+
/* ----------------------------------------------------------------
* ExecutorRun
*
@@ -824,7 +978,6 @@ ExecCheckXactReadOnly(PlannedStmt *plannedstmt)
PreventCommandIfParallelMode(CreateCommandName((Node *) plannedstmt));
}
-
/* ----------------------------------------------------------------
* InitPlan
*
@@ -838,7 +991,6 @@ InitPlan(QueryDesc *queryDesc, int eflags)
CmdType operation = queryDesc->operation;
PlannedStmt *plannedstmt = queryDesc->plannedstmt;
Plan *plan = plannedstmt->planTree;
- List *rangeTable = plannedstmt->rtable;
EState *estate = queryDesc->estate;
PlanState *planstate;
TupleDesc tupType;
@@ -846,29 +998,19 @@ InitPlan(QueryDesc *queryDesc, int eflags)
int i;
/*
- * Do permissions checks
+ * If ExecutorPrep() was not run earlier (e.g., during plan validation),
+ * perform InitPlan setup: init range table, check permissions, and run
+ * initial pruning. Otherwise, the executor will reuse the same information
+ * in queryDesc->prep->prep_estate.
*/
- ExecCheckPermissions(rangeTable, plannedstmt->permInfos, true);
-
- /*
- * initialize the node's execution state
- */
- ExecInitRangeTable(estate, rangeTable, plannedstmt->permInfos,
- bms_copy(plannedstmt->unprunableRelids));
-
- estate->es_plannedstmt = plannedstmt;
- estate->es_part_prune_infos = plannedstmt->partPruneInfos;
-
- /*
- * Perform runtime "initial" pruning to identify which child subplans,
- * corresponding to the children of plan nodes that contain
- * PartitionPruneInfo such as Append, will not be executed. The results,
- * which are bitmapsets of indexes of the child subplans that will be
- * executed, are saved in es_part_prune_results. These results correspond
- * to each PartitionPruneInfo entry, and the es_part_prune_results list is
- * parallel to es_part_prune_infos.
- */
- ExecDoInitialPruning(estate);
+ if (queryDesc->prep == NULL)
+ {
+ estate->es_plannedstmt = plannedstmt;
+ estate->es_part_prune_infos = plannedstmt->partPruneInfos;
+ PrepPlan(estate, true);
+ }
+ else
+ Assert(estate == queryDesc->prep->prep_estate);
/*
* Next, build the ExecRowMark array from the PlanRowMark(s), if any.
diff --git a/src/backend/executor/execParallel.c b/src/backend/executor/execParallel.c
index f098a5557cf..aedbd9566d6 100644
--- a/src/backend/executor/execParallel.c
+++ b/src/backend/executor/execParallel.c
@@ -1281,6 +1281,7 @@ ExecParallelGetQueryDesc(shm_toc *toc, DestReceiver *receiver,
/* Create a QueryDesc for the query. */
return CreateQueryDesc(pstmt,
+ NULL,
queryString,
GetActiveSnapshot(), InvalidSnapshot,
receiver, paramLI, NULL, instrument_options);
diff --git a/src/backend/executor/execPartition.c b/src/backend/executor/execPartition.c
index 88b150c8d77..187a480e508 100644
--- a/src/backend/executor/execPartition.c
+++ b/src/backend/executor/execPartition.c
@@ -2368,6 +2368,9 @@ InitExecPartitionPruneContexts(PartitionPruneState *prunestate,
Assert(parent_plan != NULL);
estate = parent_plan->state;
+ /* Wouldn't be available at ExecutorPrep() time. */
+ prunestate->econtext->ecxt_param_exec_vals = estate->es_param_exec_vals;
+
/*
* No need to fix subplans maps if initial pruning didn't eliminate any
* subplans.
diff --git a/src/backend/executor/functions.c b/src/backend/executor/functions.c
index 630d708d2a3..633310c5f5b 100644
--- a/src/backend/executor/functions.c
+++ b/src/backend/executor/functions.c
@@ -1362,6 +1362,7 @@ postquel_start(execution_state *es, SQLFunctionCachePtr fcache)
dest = None_Receiver;
es->qd = CreateQueryDesc(es->stmt,
+ NULL,
fcache->func->src,
GetActiveSnapshot(),
InvalidSnapshot,
diff --git a/src/backend/executor/spi.c b/src/backend/executor/spi.c
index 653500b38dc..7a3cb944d6f 100644
--- a/src/backend/executor/spi.c
+++ b/src/backend/executor/spi.c
@@ -1685,6 +1685,7 @@ SPI_cursor_open_internal(const char *name, SPIPlanPtr plan,
query_string,
plansource->commandTag,
stmt_list,
+ NIL,
cplan);
/*
@@ -2500,6 +2501,8 @@ _SPI_execute_plan(SPIPlanPtr plan, const SPIExecuteOptions *options,
CachedPlanSource *plansource = (CachedPlanSource *) lfirst(lc1);
List *stmt_list;
ListCell *lc2;
+ List *prep_list;
+ int i;
spicallbackarg.query = plansource->query_string;
@@ -2578,6 +2581,7 @@ _SPI_execute_plan(SPIPlanPtr plan, const SPIExecuteOptions *options,
plan_owner, _SPI_current->queryEnv);
stmt_list = cplan->stmt_list;
+ prep_list = NIL;
/*
* If we weren't given a specific snapshot to use, and the statement
@@ -2615,12 +2619,17 @@ _SPI_execute_plan(SPIPlanPtr plan, const SPIExecuteOptions *options,
}
}
+ i = 0;
foreach(lc2, stmt_list)
{
PlannedStmt *stmt = lfirst_node(PlannedStmt, lc2);
+ ExecPrep *prep = prep_list ?
+ list_nth(prep_list, i) : NULL;
bool canSetTag = stmt->canSetTag;
DestReceiver *dest;
+ i++;
+
/*
* Reset output state. (Note that if a non-SPI receiver is used,
* _SPI_current->processed will stay zero, and that's what we'll
@@ -2690,6 +2699,7 @@ _SPI_execute_plan(SPIPlanPtr plan, const SPIExecuteOptions *options,
snap = InvalidSnapshot;
qdesc = CreateQueryDesc(stmt,
+ prep,
plansource->query_string,
snap, crosscheck_snapshot,
dest,
diff --git a/src/backend/tcop/postgres.c b/src/backend/tcop/postgres.c
index 2bd89102686..d3964a12a14 100644
--- a/src/backend/tcop/postgres.c
+++ b/src/backend/tcop/postgres.c
@@ -1232,6 +1232,7 @@ exec_simple_query(const char *query_string)
query_string,
commandTag,
plantree_list,
+ NIL,
NULL);
/*
@@ -2033,6 +2034,7 @@ exec_bind_message(StringInfo input_message)
query_string,
psrc->commandTag,
cplan->stmt_list,
+ NIL,
cplan);
/* Portal is defined, set the plan ID based on its contents. */
diff --git a/src/backend/tcop/pquery.c b/src/backend/tcop/pquery.c
index fde78c55160..82c295502b0 100644
--- a/src/backend/tcop/pquery.c
+++ b/src/backend/tcop/pquery.c
@@ -37,6 +37,7 @@ Portal ActivePortal = NULL;
static void ProcessQuery(PlannedStmt *plan,
+ ExecPrep *prep,
const char *sourceText,
ParamListInfo params,
QueryEnvironment *queryEnv,
@@ -66,6 +67,7 @@ static void DoPortalRewind(Portal portal);
*/
QueryDesc *
CreateQueryDesc(PlannedStmt *plannedstmt,
+ ExecPrep *prep,
const char *sourceText,
Snapshot snapshot,
Snapshot crosscheck_snapshot,
@@ -78,6 +80,7 @@ CreateQueryDesc(PlannedStmt *plannedstmt,
qd->operation = plannedstmt->commandType; /* operation */
qd->plannedstmt = plannedstmt; /* plan */
+ qd->prep = prep; /* executor prep output */
qd->sourceText = sourceText; /* query text */
qd->snapshot = RegisterSnapshot(snapshot); /* snapshot */
/* RI check snapshot */
@@ -112,6 +115,13 @@ FreeQueryDesc(QueryDesc *qdesc)
UnregisterSnapshot(qdesc->snapshot);
UnregisterSnapshot(qdesc->crosscheck_snapshot);
+ /* ExecPrep cleanup if necessary */
+ if (qdesc->prep)
+ {
+ ExecPrepCleanup(qdesc->prep);
+ qdesc->prep = NULL;
+ }
+
/* Only the QueryDesc itself need be freed */
pfree(qdesc);
}
@@ -123,6 +133,7 @@ FreeQueryDesc(QueryDesc *qdesc)
* PORTAL_ONE_RETURNING, or PORTAL_ONE_MOD_WITH portal
*
* plan: the plan tree for the query
+ * prep: ExecPrep for the plan (output of ExecutorPrep())
* sourceText: the source text of the query
* params: any parameters needed
* dest: where to send results
@@ -135,6 +146,7 @@ FreeQueryDesc(QueryDesc *qdesc)
*/
static void
ProcessQuery(PlannedStmt *plan,
+ ExecPrep *prep,
const char *sourceText,
ParamListInfo params,
QueryEnvironment *queryEnv,
@@ -146,7 +158,7 @@ ProcessQuery(PlannedStmt *plan,
/*
* Create the QueryDesc object
*/
- queryDesc = CreateQueryDesc(plan, sourceText,
+ queryDesc = CreateQueryDesc(plan, prep, sourceText,
GetActiveSnapshot(), InvalidSnapshot,
dest, params, queryEnv, 0);
@@ -489,6 +501,9 @@ PortalStart(Portal portal, ParamListInfo params,
* the destination to DestNone.
*/
queryDesc = CreateQueryDesc(linitial_node(PlannedStmt, portal->stmts),
+ portal->preps ?
+ (ExecPrep *) linitial(portal->preps) :
+ NULL,
portal->sourceText,
GetActiveSnapshot(),
InvalidSnapshot,
@@ -1185,6 +1200,7 @@ PortalRunMulti(Portal portal,
{
bool active_snapshot_set = false;
ListCell *stmtlist_item;
+ int i;
/*
* If the destination is DestRemoteExecute, change to DestNone. The
@@ -1205,9 +1221,14 @@ PortalRunMulti(Portal portal,
* Loop to handle the individual queries generated from a single parsetree
* by analysis and rewrite.
*/
+ i = 0;
foreach(stmtlist_item, portal->stmts)
{
PlannedStmt *pstmt = lfirst_node(PlannedStmt, stmtlist_item);
+ ExecPrep *prep = portal->preps ?
+ list_nth(portal->preps, i) : NULL;
+
+ i++;
/*
* If we got a cancel signal in prior command, quit
@@ -1265,7 +1286,7 @@ PortalRunMulti(Portal portal,
if (pstmt->canSetTag)
{
/* statement can set tag string */
- ProcessQuery(pstmt,
+ ProcessQuery(pstmt, prep,
portal->sourceText,
portal->portalParams,
portal->queryEnv,
@@ -1274,7 +1295,7 @@ PortalRunMulti(Portal portal,
else
{
/* stmt added by rewrite cannot set tag */
- ProcessQuery(pstmt,
+ ProcessQuery(pstmt, prep,
portal->sourceText,
portal->portalParams,
portal->queryEnv,
diff --git a/src/backend/utils/mmgr/portalmem.c b/src/backend/utils/mmgr/portalmem.c
index 943da087c9f..313f8ef2fdc 100644
--- a/src/backend/utils/mmgr/portalmem.c
+++ b/src/backend/utils/mmgr/portalmem.c
@@ -284,6 +284,7 @@ PortalDefineQuery(Portal portal,
const char *sourceText,
CommandTag commandTag,
List *stmts,
+ List *preps,
CachedPlan *cplan)
{
Assert(PortalIsValid(portal));
@@ -298,6 +299,7 @@ PortalDefineQuery(Portal portal,
portal->qc.nprocessed = 0;
portal->commandTag = commandTag;
portal->stmts = stmts;
+ portal->preps = preps;
portal->cplan = cplan;
portal->status = PORTAL_DEFINED;
}
diff --git a/src/include/commands/explain.h b/src/include/commands/explain.h
index 6e51d50efc7..6aa8b275aa2 100644
--- a/src/include/commands/explain.h
+++ b/src/include/commands/explain.h
@@ -63,7 +63,8 @@ extern void ExplainOneUtility(Node *utilityStmt, IntoClause *into,
ExplainState *es, ParseState *pstate,
ParamListInfo params);
-extern void ExplainOnePlan(PlannedStmt *plannedstmt, IntoClause *into,
+extern void ExplainOnePlan(PlannedStmt *plannedstmt, ExecPrep *prep,
+ IntoClause *into,
ExplainState *es, const char *queryString,
ParamListInfo params, QueryEnvironment *queryEnv,
const instr_time *planduration,
diff --git a/src/include/executor/execdesc.h b/src/include/executor/execdesc.h
index 86db3dc8d0d..c18530f5d11 100644
--- a/src/include/executor/execdesc.h
+++ b/src/include/executor/execdesc.h
@@ -18,7 +18,6 @@
#include "nodes/execnodes.h"
#include "tcop/dest.h"
-
/* ----------------
* query descriptor:
*
@@ -35,6 +34,7 @@ typedef struct QueryDesc
/* These fields are provided by CreateQueryDesc */
CmdType operation; /* CMD_SELECT, CMD_UPDATE, etc. */
PlannedStmt *plannedstmt; /* planner's output (could be utility, too) */
+ ExecPrep *prep; /* output of ExecutorPrep() or NULL */
const char *sourceText; /* source text of the query */
Snapshot snapshot; /* snapshot to use for query */
Snapshot crosscheck_snapshot; /* crosscheck for RI update/delete */
@@ -57,6 +57,7 @@ typedef struct QueryDesc
/* in pquery.c */
extern QueryDesc *CreateQueryDesc(PlannedStmt *plannedstmt,
+ ExecPrep *prep,
const char *sourceText,
Snapshot snapshot,
Snapshot crosscheck_snapshot,
diff --git a/src/include/executor/executor.h b/src/include/executor/executor.h
index fa2b657fb2f..bc90d0ea7ee 100644
--- a/src/include/executor/executor.h
+++ b/src/include/executor/executor.h
@@ -20,6 +20,7 @@
#include "nodes/lockoptions.h"
#include "nodes/parsenodes.h"
#include "utils/memutils.h"
+#include "utils/resowner.h"
/*
@@ -234,6 +235,15 @@ ExecGetJunkAttribute(TupleTableSlot *slot, AttrNumber attno, bool *isNull)
*/
extern void ExecutorStart(QueryDesc *queryDesc, int eflags);
extern void standard_ExecutorStart(QueryDesc *queryDesc, int eflags);
+
+extern ExecPrep *ExecutorPrep(PlannedStmt *pstmt,
+ ParamListInfo params,
+ ResourceOwner owner,
+ bool do_initial_pruning);
+extern ExecPrep *CreateExecPrep(EState *estate, MemoryContext context,
+ execprep_cleanup_fn cleanup, void *cleanup_arg);
+extern void ExecPrepCleanup(ExecPrep *prep);
+
extern void ExecutorRun(QueryDesc *queryDesc,
ScanDirection direction, uint64 count);
extern void standard_ExecutorRun(QueryDesc *queryDesc,
diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h
index 18ae8f0d4bb..f569be3853f 100644
--- a/src/include/nodes/execnodes.h
+++ b/src/include/nodes/execnodes.h
@@ -772,6 +772,61 @@ typedef struct EState
List *es_insert_pending_modifytables;
} EState;
+/*
+ * ExecPrep: encapsulates executor preparation results for a PlannedStmt.
+ *
+ * This is used when we want to perform executor setup steps -- such as
+ * initializing the range table, checking permissions, and executing initial
+ * partition pruning -- ahead of actual plan execution. A typical use case is
+ * in plan validation logic (e.g., when deciding whether to reuse a generic
+ * cached plan), where we need to determine exactly which partitions will be
+ * scanned and locked, without executing the full plan.
+ *
+ * The executor may later adopt the prepared EState (via ExecutorStart),
+ * avoiding redundant setup. In that case, the executor is responsible for
+ * freeing the state and ExecPrepCleanup() will skip it.
+ */
+struct ExecPrep;
+
+/*
+ * Optional callback to clean up user-specific resources associated with
+ * ExecPrep.
+ */
+typedef void (*execprep_cleanup_fn)(struct ExecPrep *prep);
+
+/* ExecutorPrep output */
+typedef struct ExecPrep
+{
+ /*
+ * Context in which this struct and all subsidiary allocations were made.
+ * This context must remain alive until ExecPrepCleanup is called.
+ */
+ MemoryContext context;
+
+ /*
+ * Partially-initialized executor state used for permission checks and
+ * pruning. May be adopted directly by ExecutorStart(), in which case
+ * ExecPrepCleanup will skip freeing it.
+ */
+ EState *prep_estate;
+
+ /*
+ * True if ExecPrepCleanup() must free the EState. If the executor adopts
+ * prep_estate, this is set to false to avoid double-free.
+ */
+ bool owns_estate;
+
+ /*
+ * Optional caller-supplied cleanup hook to run during ExecPrepCleanup.
+ * Useful for releasing external resources associated with the prep.
+ */
+ execprep_cleanup_fn cleanup;
+
+ /*
+ * Opaque pointer to pass to the cleanup hook.
+ */
+ void *cleanup_arg;
+} ExecPrep;
/*
* ExecRowMark -
diff --git a/src/include/utils/portal.h b/src/include/utils/portal.h
index 5ffa6fd5cc8..013bcc3bd8e 100644
--- a/src/include/utils/portal.h
+++ b/src/include/utils/portal.h
@@ -137,6 +137,7 @@ typedef struct PortalData
CommandTag commandTag; /* command tag for original query */
QueryCompletion qc; /* command completion data for executed query */
List *stmts; /* list of PlannedStmts */
+ List *preps; /* list of ExecPreps where needed */
CachedPlan *cplan; /* CachedPlan, if stmts are from one */
ParamListInfo portalParams; /* params to pass to query */
@@ -240,6 +241,7 @@ extern void PortalDefineQuery(Portal portal,
const char *sourceText,
CommandTag commandTag,
List *stmts,
+ List *preps,
CachedPlan *cplan);
extern PlannedStmt *PortalGetPrimaryStmt(Portal portal);
extern void PortalCreateHoldStore(Portal portal);
--
2.47.3
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Subject: Re: generic plans and "initial" pruning
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