public inbox for [email protected]help / color / mirror / Atom feed
Re: Using Expanded Objects other than Arrays from plpgsql 2+ messages / 2 participants [nested] [flat]
* Re: Using Expanded Objects other than Arrays from plpgsql @ 2024-10-20 19:19 Tom Lane <[email protected]> 0 siblings, 0 replies; 2+ messages in thread From: Tom Lane @ 2024-10-20 19:19 UTC (permalink / raw) To: Michel Pelletier <[email protected]>; +Cc: pgsql-general <[email protected]> Michel Pelletier <[email protected]> writes: > On Sun, Oct 20, 2024 at 10:13 AM Tom Lane <[email protected]> wrote: >> The other problem is that plpgsql only knows how to do such expansion >> for arrays, and it's not obvious how to extend that part. > Perhaps a third member function for ExpandedObjectMethods that formalizes > the expansion interface like found in DatumGetExpandedArray? I closely > follow that same pattern in my code. The trouble is we don't have an expanded object to consult at this point --- only a flat Datum. plpgsql has hard-wired knowledge that it's okay to apply expand_array if the datatype passes the typisarray tests, but I'm pretty unclear on how to provide similar knowledge for extension datatypes. regards, tom lane ^ permalink raw reply [nested|flat] 2+ messages in thread
* [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic @ 2026-07-09 18:57 Nathan Bossart <[email protected]> 0 siblings, 0 replies; 2+ messages in thread From: Nathan Bossart @ 2026-07-09 18:57 UTC (permalink / raw) --- src/backend/access/transam/parallel.c | 22 ++++++++-------------- 1 file changed, 8 insertions(+), 14 deletions(-) diff --git a/src/backend/access/transam/parallel.c b/src/backend/access/transam/parallel.c index 89e9d224eec..57f5f26bbec 100644 --- a/src/backend/access/transam/parallel.c +++ b/src/backend/access/transam/parallel.c @@ -37,7 +37,6 @@ #include "storage/ipc.h" #include "storage/predicate.h" #include "storage/proc.h" -#include "storage/spin.h" #include "tcop/tcopprot.h" #include "utils/combocid.h" #include "utils/guc.h" @@ -101,11 +100,8 @@ typedef struct FixedParallelState TimestampTz stmt_ts; SerializableXactHandle serializable_xact_handle; - /* Mutex protects remaining fields. */ - slock_t mutex; - /* Maximum XactLastRecEnd of any worker. */ - XLogRecPtr last_xlog_end; + pg_atomic_uint64 last_xlog_end; } FixedParallelState; /* @@ -358,8 +354,7 @@ InitializeParallelDSM(ParallelContext *pcxt) fps->xact_ts = GetCurrentTransactionStartTimestamp(); fps->stmt_ts = GetCurrentStatementStartTimestamp(); fps->serializable_xact_handle = ShareSerializableXact(); - SpinLockInit(&fps->mutex); - fps->last_xlog_end = InvalidXLogRecPtr; + pg_atomic_init_u64(&fps->last_xlog_end, InvalidXLogRecPtr); shm_toc_insert(pcxt->toc, PARALLEL_KEY_FIXED, fps); /* We can skip the rest of this if we're not budgeting for any workers. */ @@ -532,7 +527,7 @@ ReinitializeParallelDSM(ParallelContext *pcxt) /* Reset a few bits of fixed parallel state to a clean state. */ fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false); - fps->last_xlog_end = InvalidXLogRecPtr; + pg_atomic_write_u64(&fps->last_xlog_end, InvalidXLogRecPtr); /* Recreate error queues (if they exist). */ if (pcxt->nworkers > 0) @@ -900,10 +895,12 @@ WaitForParallelWorkersToFinish(ParallelContext *pcxt) if (pcxt->toc != NULL) { FixedParallelState *fps; + XLogRecPtr last_xlog_end; fps = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_FIXED, false); - if (fps->last_xlog_end > XactLastRecEnd) - XactLastRecEnd = fps->last_xlog_end; + last_xlog_end = pg_atomic_read_u64(&fps->last_xlog_end); + if (last_xlog_end > XactLastRecEnd) + XactLastRecEnd = last_xlog_end; } } @@ -1596,10 +1593,7 @@ ParallelWorkerReportLastRecEnd(XLogRecPtr last_xlog_end) FixedParallelState *fps = MyFixedParallelState; Assert(fps != NULL); - SpinLockAcquire(&fps->mutex); - if (fps->last_xlog_end < last_xlog_end) - fps->last_xlog_end = last_xlog_end; - SpinLockRelease(&fps->mutex); + pg_atomic_monotonic_advance_u64(&fps->last_xlog_end, last_xlog_end); } /* -- 2.50.1 (Apple Git-155) --Ot5x3ffkWEuxilWO Content-Type: text/plain; charset=us-ascii Content-Disposition: attachment; filename=v1-0004-convert-PROC_HDR-startupBufferPinWaitBufId-to-an-.patch ^ permalink raw reply [nested|flat] 2+ messages in thread
end of thread, other threads:[~2026-07-09 18:57 UTC | newest] Thread overview: 2+ messages (download: mbox mbox.gz follow: Atom feed) -- links below jump to the message on this page -- 2024-10-20 19:19 Re: Using Expanded Objects other than Arrays from plpgsql Tom Lane <[email protected]> 2026-07-09 18:57 [PATCH v1 3/8] convert FixedParallelState->last_xlog_end to an atomic Nathan Bossart <[email protected]>
This inbox is served by agora; see mirroring instructions for how to clone and mirror all data and code used for this inbox