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[PATCH v3 3/3] Fix sizing of tape read buffers.
23+ messages / 3 participants
[nested] [flat]

* [PATCH v3 3/3] Fix sizing of tape read buffers.
@ 2021-01-22 20:59  Heikki Linnakangas <[email protected]>
  0 siblings, 0 replies; 23+ messages in thread

From: Heikki Linnakangas @ 2021-01-22 20:59 UTC (permalink / raw)

---
 src/backend/utils/sort/tuplesort.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/backend/utils/sort/tuplesort.c b/src/backend/utils/sort/tuplesort.c
index 14104643e78..aff2f201f52 100644
--- a/src/backend/utils/sort/tuplesort.c
+++ b/src/backend/utils/sort/tuplesort.c
@@ -2658,7 +2658,7 @@ merge_read_buffer_size(int64 avail_mem, int nInputTapes, int nInputRuns,
 	 * we derive the input buffer size from the amount of memory available,
 	 * and M and N.
 	 */
-	return (avail_mem - TAPE_BUFFER_OVERHEAD * nOutputTapes) / nInputTapes;
+	return Max((avail_mem - TAPE_BUFFER_OVERHEAD * nOutputTapes) / nInputTapes, 0);
 }
 
 /*
-- 
2.29.2


--------------631E0A48DCAEA386819DFCEC--





^ permalink  raw  reply  [nested|flat] 23+ messages in thread

* [PATCH v3 3/3] Fix sizing of tape read buffers.
@ 2021-01-22 20:59  Heikki Linnakangas <[email protected]>
  0 siblings, 0 replies; 23+ messages in thread

From: Heikki Linnakangas @ 2021-01-22 20:59 UTC (permalink / raw)

---
 src/backend/utils/sort/tuplesort.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/backend/utils/sort/tuplesort.c b/src/backend/utils/sort/tuplesort.c
index 14104643e78..aff2f201f52 100644
--- a/src/backend/utils/sort/tuplesort.c
+++ b/src/backend/utils/sort/tuplesort.c
@@ -2658,7 +2658,7 @@ merge_read_buffer_size(int64 avail_mem, int nInputTapes, int nInputRuns,
 	 * we derive the input buffer size from the amount of memory available,
 	 * and M and N.
 	 */
-	return (avail_mem - TAPE_BUFFER_OVERHEAD * nOutputTapes) / nInputTapes;
+	return Max((avail_mem - TAPE_BUFFER_OVERHEAD * nOutputTapes) / nInputTapes, 0);
 }
 
 /*
-- 
2.29.2


--------------631E0A48DCAEA386819DFCEC--





^ permalink  raw  reply  [nested|flat] 23+ messages in thread

* [PATCH v3 3/3] Fix sizing of tape read buffers.
@ 2021-01-22 20:59  Heikki Linnakangas <[email protected]>
  0 siblings, 0 replies; 23+ messages in thread

From: Heikki Linnakangas @ 2021-01-22 20:59 UTC (permalink / raw)

---
 src/backend/utils/sort/tuplesort.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/backend/utils/sort/tuplesort.c b/src/backend/utils/sort/tuplesort.c
index 14104643e78..aff2f201f52 100644
--- a/src/backend/utils/sort/tuplesort.c
+++ b/src/backend/utils/sort/tuplesort.c
@@ -2658,7 +2658,7 @@ merge_read_buffer_size(int64 avail_mem, int nInputTapes, int nInputRuns,
 	 * we derive the input buffer size from the amount of memory available,
 	 * and M and N.
 	 */
-	return (avail_mem - TAPE_BUFFER_OVERHEAD * nOutputTapes) / nInputTapes;
+	return Max((avail_mem - TAPE_BUFFER_OVERHEAD * nOutputTapes) / nInputTapes, 0);
 }
 
 /*
-- 
2.29.2


--------------631E0A48DCAEA386819DFCEC--





^ permalink  raw  reply  [nested|flat] 23+ messages in thread

* [PATCH v3 3/3] Fix sizing of tape read buffers.
@ 2021-01-22 20:59  Heikki Linnakangas <[email protected]>
  0 siblings, 0 replies; 23+ messages in thread

From: Heikki Linnakangas @ 2021-01-22 20:59 UTC (permalink / raw)

---
 src/backend/utils/sort/tuplesort.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/backend/utils/sort/tuplesort.c b/src/backend/utils/sort/tuplesort.c
index 14104643e78..aff2f201f52 100644
--- a/src/backend/utils/sort/tuplesort.c
+++ b/src/backend/utils/sort/tuplesort.c
@@ -2658,7 +2658,7 @@ merge_read_buffer_size(int64 avail_mem, int nInputTapes, int nInputRuns,
 	 * we derive the input buffer size from the amount of memory available,
 	 * and M and N.
 	 */
-	return (avail_mem - TAPE_BUFFER_OVERHEAD * nOutputTapes) / nInputTapes;
+	return Max((avail_mem - TAPE_BUFFER_OVERHEAD * nOutputTapes) / nInputTapes, 0);
 }
 
 /*
-- 
2.29.2


--------------631E0A48DCAEA386819DFCEC--





^ permalink  raw  reply  [nested|flat] 23+ messages in thread

* [PATCH v3 3/3] Fix sizing of tape read buffers.
@ 2021-01-22 20:59  Heikki Linnakangas <[email protected]>
  0 siblings, 0 replies; 23+ messages in thread

From: Heikki Linnakangas @ 2021-01-22 20:59 UTC (permalink / raw)

---
 src/backend/utils/sort/tuplesort.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/backend/utils/sort/tuplesort.c b/src/backend/utils/sort/tuplesort.c
index 14104643e78..aff2f201f52 100644
--- a/src/backend/utils/sort/tuplesort.c
+++ b/src/backend/utils/sort/tuplesort.c
@@ -2658,7 +2658,7 @@ merge_read_buffer_size(int64 avail_mem, int nInputTapes, int nInputRuns,
 	 * we derive the input buffer size from the amount of memory available,
 	 * and M and N.
 	 */
-	return (avail_mem - TAPE_BUFFER_OVERHEAD * nOutputTapes) / nInputTapes;
+	return Max((avail_mem - TAPE_BUFFER_OVERHEAD * nOutputTapes) / nInputTapes, 0);
 }
 
 /*
-- 
2.29.2


--------------631E0A48DCAEA386819DFCEC--





^ permalink  raw  reply  [nested|flat] 23+ messages in thread

* [PATCH v3 3/3] Fix sizing of tape read buffers.
@ 2021-01-22 20:59  Heikki Linnakangas <[email protected]>
  0 siblings, 0 replies; 23+ messages in thread

From: Heikki Linnakangas @ 2021-01-22 20:59 UTC (permalink / raw)

---
 src/backend/utils/sort/tuplesort.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/backend/utils/sort/tuplesort.c b/src/backend/utils/sort/tuplesort.c
index 14104643e78..aff2f201f52 100644
--- a/src/backend/utils/sort/tuplesort.c
+++ b/src/backend/utils/sort/tuplesort.c
@@ -2658,7 +2658,7 @@ merge_read_buffer_size(int64 avail_mem, int nInputTapes, int nInputRuns,
 	 * we derive the input buffer size from the amount of memory available,
 	 * and M and N.
 	 */
-	return (avail_mem - TAPE_BUFFER_OVERHEAD * nOutputTapes) / nInputTapes;
+	return Max((avail_mem - TAPE_BUFFER_OVERHEAD * nOutputTapes) / nInputTapes, 0);
 }
 
 /*
-- 
2.29.2


--------------631E0A48DCAEA386819DFCEC--





^ permalink  raw  reply  [nested|flat] 23+ messages in thread

* [PATCH v3 3/3] Fix sizing of tape read buffers.
@ 2021-01-22 20:59  Heikki Linnakangas <[email protected]>
  0 siblings, 0 replies; 23+ messages in thread

From: Heikki Linnakangas @ 2021-01-22 20:59 UTC (permalink / raw)

---
 src/backend/utils/sort/tuplesort.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/backend/utils/sort/tuplesort.c b/src/backend/utils/sort/tuplesort.c
index 14104643e78..aff2f201f52 100644
--- a/src/backend/utils/sort/tuplesort.c
+++ b/src/backend/utils/sort/tuplesort.c
@@ -2658,7 +2658,7 @@ merge_read_buffer_size(int64 avail_mem, int nInputTapes, int nInputRuns,
 	 * we derive the input buffer size from the amount of memory available,
 	 * and M and N.
 	 */
-	return (avail_mem - TAPE_BUFFER_OVERHEAD * nOutputTapes) / nInputTapes;
+	return Max((avail_mem - TAPE_BUFFER_OVERHEAD * nOutputTapes) / nInputTapes, 0);
 }
 
 /*
-- 
2.29.2


--------------631E0A48DCAEA386819DFCEC--





^ permalink  raw  reply  [nested|flat] 23+ messages in thread

* [PATCH v3 3/3] Fix sizing of tape read buffers.
@ 2021-01-22 20:59  Heikki Linnakangas <[email protected]>
  0 siblings, 0 replies; 23+ messages in thread

From: Heikki Linnakangas @ 2021-01-22 20:59 UTC (permalink / raw)

---
 src/backend/utils/sort/tuplesort.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/backend/utils/sort/tuplesort.c b/src/backend/utils/sort/tuplesort.c
index 14104643e78..aff2f201f52 100644
--- a/src/backend/utils/sort/tuplesort.c
+++ b/src/backend/utils/sort/tuplesort.c
@@ -2658,7 +2658,7 @@ merge_read_buffer_size(int64 avail_mem, int nInputTapes, int nInputRuns,
 	 * we derive the input buffer size from the amount of memory available,
 	 * and M and N.
 	 */
-	return (avail_mem - TAPE_BUFFER_OVERHEAD * nOutputTapes) / nInputTapes;
+	return Max((avail_mem - TAPE_BUFFER_OVERHEAD * nOutputTapes) / nInputTapes, 0);
 }
 
 /*
-- 
2.29.2


--------------631E0A48DCAEA386819DFCEC--





^ permalink  raw  reply  [nested|flat] 23+ messages in thread

* [PATCH v3 3/3] Fix sizing of tape read buffers.
@ 2021-01-22 20:59  Heikki Linnakangas <[email protected]>
  0 siblings, 0 replies; 23+ messages in thread

From: Heikki Linnakangas @ 2021-01-22 20:59 UTC (permalink / raw)

---
 src/backend/utils/sort/tuplesort.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/backend/utils/sort/tuplesort.c b/src/backend/utils/sort/tuplesort.c
index 14104643e78..aff2f201f52 100644
--- a/src/backend/utils/sort/tuplesort.c
+++ b/src/backend/utils/sort/tuplesort.c
@@ -2658,7 +2658,7 @@ merge_read_buffer_size(int64 avail_mem, int nInputTapes, int nInputRuns,
 	 * we derive the input buffer size from the amount of memory available,
 	 * and M and N.
 	 */
-	return (avail_mem - TAPE_BUFFER_OVERHEAD * nOutputTapes) / nInputTapes;
+	return Max((avail_mem - TAPE_BUFFER_OVERHEAD * nOutputTapes) / nInputTapes, 0);
 }
 
 /*
-- 
2.29.2


--------------631E0A48DCAEA386819DFCEC--





^ permalink  raw  reply  [nested|flat] 23+ messages in thread

* [PATCH v3 3/3] Fix sizing of tape read buffers.
@ 2021-01-22 20:59  Heikki Linnakangas <[email protected]>
  0 siblings, 0 replies; 23+ messages in thread

From: Heikki Linnakangas @ 2021-01-22 20:59 UTC (permalink / raw)

---
 src/backend/utils/sort/tuplesort.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/backend/utils/sort/tuplesort.c b/src/backend/utils/sort/tuplesort.c
index 14104643e78..aff2f201f52 100644
--- a/src/backend/utils/sort/tuplesort.c
+++ b/src/backend/utils/sort/tuplesort.c
@@ -2658,7 +2658,7 @@ merge_read_buffer_size(int64 avail_mem, int nInputTapes, int nInputRuns,
 	 * we derive the input buffer size from the amount of memory available,
 	 * and M and N.
 	 */
-	return (avail_mem - TAPE_BUFFER_OVERHEAD * nOutputTapes) / nInputTapes;
+	return Max((avail_mem - TAPE_BUFFER_OVERHEAD * nOutputTapes) / nInputTapes, 0);
 }
 
 /*
-- 
2.29.2


--------------631E0A48DCAEA386819DFCEC--





^ permalink  raw  reply  [nested|flat] 23+ messages in thread

* [PATCH v3 3/3] Fix sizing of tape read buffers.
@ 2021-01-22 20:59  Heikki Linnakangas <[email protected]>
  0 siblings, 0 replies; 23+ messages in thread

From: Heikki Linnakangas @ 2021-01-22 20:59 UTC (permalink / raw)

---
 src/backend/utils/sort/tuplesort.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/backend/utils/sort/tuplesort.c b/src/backend/utils/sort/tuplesort.c
index 14104643e78..aff2f201f52 100644
--- a/src/backend/utils/sort/tuplesort.c
+++ b/src/backend/utils/sort/tuplesort.c
@@ -2658,7 +2658,7 @@ merge_read_buffer_size(int64 avail_mem, int nInputTapes, int nInputRuns,
 	 * we derive the input buffer size from the amount of memory available,
 	 * and M and N.
 	 */
-	return (avail_mem - TAPE_BUFFER_OVERHEAD * nOutputTapes) / nInputTapes;
+	return Max((avail_mem - TAPE_BUFFER_OVERHEAD * nOutputTapes) / nInputTapes, 0);
 }
 
 /*
-- 
2.29.2


--------------631E0A48DCAEA386819DFCEC--





^ permalink  raw  reply  [nested|flat] 23+ messages in thread

* [PATCH v3 3/3] Fix sizing of tape read buffers.
@ 2021-01-22 20:59  Heikki Linnakangas <[email protected]>
  0 siblings, 0 replies; 23+ messages in thread

From: Heikki Linnakangas @ 2021-01-22 20:59 UTC (permalink / raw)

---
 src/backend/utils/sort/tuplesort.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/backend/utils/sort/tuplesort.c b/src/backend/utils/sort/tuplesort.c
index 14104643e78..aff2f201f52 100644
--- a/src/backend/utils/sort/tuplesort.c
+++ b/src/backend/utils/sort/tuplesort.c
@@ -2658,7 +2658,7 @@ merge_read_buffer_size(int64 avail_mem, int nInputTapes, int nInputRuns,
 	 * we derive the input buffer size from the amount of memory available,
 	 * and M and N.
 	 */
-	return (avail_mem - TAPE_BUFFER_OVERHEAD * nOutputTapes) / nInputTapes;
+	return Max((avail_mem - TAPE_BUFFER_OVERHEAD * nOutputTapes) / nInputTapes, 0);
 }
 
 /*
-- 
2.29.2


--------------631E0A48DCAEA386819DFCEC--





^ permalink  raw  reply  [nested|flat] 23+ messages in thread

* [PATCH v3 3/3] Fix sizing of tape read buffers.
@ 2021-01-22 20:59  Heikki Linnakangas <[email protected]>
  0 siblings, 0 replies; 23+ messages in thread

From: Heikki Linnakangas @ 2021-01-22 20:59 UTC (permalink / raw)

---
 src/backend/utils/sort/tuplesort.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/backend/utils/sort/tuplesort.c b/src/backend/utils/sort/tuplesort.c
index 14104643e78..aff2f201f52 100644
--- a/src/backend/utils/sort/tuplesort.c
+++ b/src/backend/utils/sort/tuplesort.c
@@ -2658,7 +2658,7 @@ merge_read_buffer_size(int64 avail_mem, int nInputTapes, int nInputRuns,
 	 * we derive the input buffer size from the amount of memory available,
 	 * and M and N.
 	 */
-	return (avail_mem - TAPE_BUFFER_OVERHEAD * nOutputTapes) / nInputTapes;
+	return Max((avail_mem - TAPE_BUFFER_OVERHEAD * nOutputTapes) / nInputTapes, 0);
 }
 
 /*
-- 
2.29.2


--------------631E0A48DCAEA386819DFCEC--





^ permalink  raw  reply  [nested|flat] 23+ messages in thread

* [PATCH v3 3/3] Fix sizing of tape read buffers.
@ 2021-01-22 20:59  Heikki Linnakangas <[email protected]>
  0 siblings, 0 replies; 23+ messages in thread

From: Heikki Linnakangas @ 2021-01-22 20:59 UTC (permalink / raw)

---
 src/backend/utils/sort/tuplesort.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/backend/utils/sort/tuplesort.c b/src/backend/utils/sort/tuplesort.c
index 14104643e78..aff2f201f52 100644
--- a/src/backend/utils/sort/tuplesort.c
+++ b/src/backend/utils/sort/tuplesort.c
@@ -2658,7 +2658,7 @@ merge_read_buffer_size(int64 avail_mem, int nInputTapes, int nInputRuns,
 	 * we derive the input buffer size from the amount of memory available,
 	 * and M and N.
 	 */
-	return (avail_mem - TAPE_BUFFER_OVERHEAD * nOutputTapes) / nInputTapes;
+	return Max((avail_mem - TAPE_BUFFER_OVERHEAD * nOutputTapes) / nInputTapes, 0);
 }
 
 /*
-- 
2.29.2


--------------631E0A48DCAEA386819DFCEC--





^ permalink  raw  reply  [nested|flat] 23+ messages in thread

* [PATCH v3 3/3] Fix sizing of tape read buffers.
@ 2021-01-22 20:59  Heikki Linnakangas <[email protected]>
  0 siblings, 0 replies; 23+ messages in thread

From: Heikki Linnakangas @ 2021-01-22 20:59 UTC (permalink / raw)

---
 src/backend/utils/sort/tuplesort.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/backend/utils/sort/tuplesort.c b/src/backend/utils/sort/tuplesort.c
index 14104643e78..aff2f201f52 100644
--- a/src/backend/utils/sort/tuplesort.c
+++ b/src/backend/utils/sort/tuplesort.c
@@ -2658,7 +2658,7 @@ merge_read_buffer_size(int64 avail_mem, int nInputTapes, int nInputRuns,
 	 * we derive the input buffer size from the amount of memory available,
 	 * and M and N.
 	 */
-	return (avail_mem - TAPE_BUFFER_OVERHEAD * nOutputTapes) / nInputTapes;
+	return Max((avail_mem - TAPE_BUFFER_OVERHEAD * nOutputTapes) / nInputTapes, 0);
 }
 
 /*
-- 
2.29.2


--------------631E0A48DCAEA386819DFCEC--





^ permalink  raw  reply  [nested|flat] 23+ messages in thread

* [PATCH v3 3/3] Fix sizing of tape read buffers.
@ 2021-01-22 20:59  Heikki Linnakangas <[email protected]>
  0 siblings, 0 replies; 23+ messages in thread

From: Heikki Linnakangas @ 2021-01-22 20:59 UTC (permalink / raw)

---
 src/backend/utils/sort/tuplesort.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/backend/utils/sort/tuplesort.c b/src/backend/utils/sort/tuplesort.c
index 14104643e78..aff2f201f52 100644
--- a/src/backend/utils/sort/tuplesort.c
+++ b/src/backend/utils/sort/tuplesort.c
@@ -2658,7 +2658,7 @@ merge_read_buffer_size(int64 avail_mem, int nInputTapes, int nInputRuns,
 	 * we derive the input buffer size from the amount of memory available,
 	 * and M and N.
 	 */
-	return (avail_mem - TAPE_BUFFER_OVERHEAD * nOutputTapes) / nInputTapes;
+	return Max((avail_mem - TAPE_BUFFER_OVERHEAD * nOutputTapes) / nInputTapes, 0);
 }
 
 /*
-- 
2.29.2


--------------631E0A48DCAEA386819DFCEC--





^ permalink  raw  reply  [nested|flat] 23+ messages in thread

* [PATCH v3 3/3] Fix sizing of tape read buffers.
@ 2021-01-22 20:59  Heikki Linnakangas <[email protected]>
  0 siblings, 0 replies; 23+ messages in thread

From: Heikki Linnakangas @ 2021-01-22 20:59 UTC (permalink / raw)

---
 src/backend/utils/sort/tuplesort.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/backend/utils/sort/tuplesort.c b/src/backend/utils/sort/tuplesort.c
index 14104643e78..aff2f201f52 100644
--- a/src/backend/utils/sort/tuplesort.c
+++ b/src/backend/utils/sort/tuplesort.c
@@ -2658,7 +2658,7 @@ merge_read_buffer_size(int64 avail_mem, int nInputTapes, int nInputRuns,
 	 * we derive the input buffer size from the amount of memory available,
 	 * and M and N.
 	 */
-	return (avail_mem - TAPE_BUFFER_OVERHEAD * nOutputTapes) / nInputTapes;
+	return Max((avail_mem - TAPE_BUFFER_OVERHEAD * nOutputTapes) / nInputTapes, 0);
 }
 
 /*
-- 
2.29.2


--------------631E0A48DCAEA386819DFCEC--





^ permalink  raw  reply  [nested|flat] 23+ messages in thread

* [PATCH v3 3/3] Fix sizing of tape read buffers.
@ 2021-01-22 20:59  Heikki Linnakangas <[email protected]>
  0 siblings, 0 replies; 23+ messages in thread

From: Heikki Linnakangas @ 2021-01-22 20:59 UTC (permalink / raw)

---
 src/backend/utils/sort/tuplesort.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/backend/utils/sort/tuplesort.c b/src/backend/utils/sort/tuplesort.c
index 14104643e78..aff2f201f52 100644
--- a/src/backend/utils/sort/tuplesort.c
+++ b/src/backend/utils/sort/tuplesort.c
@@ -2658,7 +2658,7 @@ merge_read_buffer_size(int64 avail_mem, int nInputTapes, int nInputRuns,
 	 * we derive the input buffer size from the amount of memory available,
 	 * and M and N.
 	 */
-	return (avail_mem - TAPE_BUFFER_OVERHEAD * nOutputTapes) / nInputTapes;
+	return Max((avail_mem - TAPE_BUFFER_OVERHEAD * nOutputTapes) / nInputTapes, 0);
 }
 
 /*
-- 
2.29.2


--------------631E0A48DCAEA386819DFCEC--





^ permalink  raw  reply  [nested|flat] 23+ messages in thread

* [PATCH v3 3/3] Fix sizing of tape read buffers.
@ 2021-01-22 20:59  Heikki Linnakangas <[email protected]>
  0 siblings, 0 replies; 23+ messages in thread

From: Heikki Linnakangas @ 2021-01-22 20:59 UTC (permalink / raw)

---
 src/backend/utils/sort/tuplesort.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/backend/utils/sort/tuplesort.c b/src/backend/utils/sort/tuplesort.c
index 14104643e78..aff2f201f52 100644
--- a/src/backend/utils/sort/tuplesort.c
+++ b/src/backend/utils/sort/tuplesort.c
@@ -2658,7 +2658,7 @@ merge_read_buffer_size(int64 avail_mem, int nInputTapes, int nInputRuns,
 	 * we derive the input buffer size from the amount of memory available,
 	 * and M and N.
 	 */
-	return (avail_mem - TAPE_BUFFER_OVERHEAD * nOutputTapes) / nInputTapes;
+	return Max((avail_mem - TAPE_BUFFER_OVERHEAD * nOutputTapes) / nInputTapes, 0);
 }
 
 /*
-- 
2.29.2


--------------631E0A48DCAEA386819DFCEC--





^ permalink  raw  reply  [nested|flat] 23+ messages in thread

* [PATCH v3 3/3] Fix sizing of tape read buffers.
@ 2021-01-22 20:59  Heikki Linnakangas <[email protected]>
  0 siblings, 0 replies; 23+ messages in thread

From: Heikki Linnakangas @ 2021-01-22 20:59 UTC (permalink / raw)

---
 src/backend/utils/sort/tuplesort.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/backend/utils/sort/tuplesort.c b/src/backend/utils/sort/tuplesort.c
index 14104643e78..aff2f201f52 100644
--- a/src/backend/utils/sort/tuplesort.c
+++ b/src/backend/utils/sort/tuplesort.c
@@ -2658,7 +2658,7 @@ merge_read_buffer_size(int64 avail_mem, int nInputTapes, int nInputRuns,
 	 * we derive the input buffer size from the amount of memory available,
 	 * and M and N.
 	 */
-	return (avail_mem - TAPE_BUFFER_OVERHEAD * nOutputTapes) / nInputTapes;
+	return Max((avail_mem - TAPE_BUFFER_OVERHEAD * nOutputTapes) / nInputTapes, 0);
 }
 
 /*
-- 
2.29.2


--------------631E0A48DCAEA386819DFCEC--





^ permalink  raw  reply  [nested|flat] 23+ messages in thread

* [PATCH v3 3/3] Fix sizing of tape read buffers.
@ 2021-01-22 20:59  Heikki Linnakangas <[email protected]>
  0 siblings, 0 replies; 23+ messages in thread

From: Heikki Linnakangas @ 2021-01-22 20:59 UTC (permalink / raw)

---
 src/backend/utils/sort/tuplesort.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/backend/utils/sort/tuplesort.c b/src/backend/utils/sort/tuplesort.c
index 14104643e78..aff2f201f52 100644
--- a/src/backend/utils/sort/tuplesort.c
+++ b/src/backend/utils/sort/tuplesort.c
@@ -2658,7 +2658,7 @@ merge_read_buffer_size(int64 avail_mem, int nInputTapes, int nInputRuns,
 	 * we derive the input buffer size from the amount of memory available,
 	 * and M and N.
 	 */
-	return (avail_mem - TAPE_BUFFER_OVERHEAD * nOutputTapes) / nInputTapes;
+	return Max((avail_mem - TAPE_BUFFER_OVERHEAD * nOutputTapes) / nInputTapes, 0);
 }
 
 /*
-- 
2.29.2


--------------631E0A48DCAEA386819DFCEC--





^ permalink  raw  reply  [nested|flat] 23+ messages in thread

* Re: pg17.3 PQescapeIdentifier() ignores len
@ 2025-02-13 16:59  Ranier Vilela <[email protected]>
  0 siblings, 1 reply; 23+ messages in thread

From: Ranier Vilela @ 2025-02-13 16:59 UTC (permalink / raw)
  To: Justin Pryzby <[email protected]>; +Cc: [email protected]

Em qui., 13 de fev. de 2025 às 13:51, Justin Pryzby <[email protected]>
escreveu:

> I found errors in our sql log after upgrading to 17.3.
>
> error_severity | ERROR
> message        | schema
> "rptcache.44e3955c33bb79f55750897da0c5ab1fa2004af1_20250214" does not exist
> query          | copy
> "rptcache.44e3955c33bb79f55750897da0c5ab1fa2004af1_20250214"."44e3955c33bb79f55750897da0c5ab1fa2004af1_20250214"
> from stdin
>
> The copy command is from pygresql's inserttable(), which does:
>
>     do {
>         t = strchr(s, '.');
>         if (!t)
>             t = s + strlen(s);
>         table = PQescapeIdentifier(self->cnx, s, (size_t)(t - s));
>         fprintf(stderr, "table %s len %ld => %s\n", s, t-s, table);
>         if (bufpt < bufmax)
>             bufpt += snprintf(bufpt, (size_t)(bufmax - bufpt), "%s",
> table);
>         PQfreemem(table);
>         s = t;
>         if (*s && bufpt < bufmax)
>             *bufpt++ = *s++;
>     } while (*s);
>
> The fprintf suggests that since 5dc1e42b4 PQescapeIdentifier ignores its
> len.
>
Interesting, Coverity has some new reports regarding PQescapeIdentifier.

CID 1591290: (#1 of 1): Out-of-bounds access (OVERRUN)
2. alloc_strlen: Allocating insufficient memory for the terminating null of
the string. [Note: The source code implementation of the function has been
overridden by a builtin model.]

Until now, I was in disbelief.

best regards,
Ranier Vilela


^ permalink  raw  reply  [nested|flat] 23+ messages in thread

* Re: pg17.3 PQescapeIdentifier() ignores len
@ 2025-02-13 19:05  Tom Lane <[email protected]>
  parent: Ranier Vilela <[email protected]>
  0 siblings, 0 replies; 23+ messages in thread

From: Tom Lane @ 2025-02-13 19:05 UTC (permalink / raw)
  To: Ranier Vilela <[email protected]>; +Cc: Justin Pryzby <[email protected]>; [email protected]

Ranier Vilela <[email protected]> writes:
> Interesting, Coverity has some new reports regarding PQescapeIdentifier.

> CID 1591290: (#1 of 1): Out-of-bounds access (OVERRUN)
> 2. alloc_strlen: Allocating insufficient memory for the terminating null of
> the string. [Note: The source code implementation of the function has been
> overridden by a builtin model.]

That's not new, we've been seeing those for awhile.  I've been
ignoring them on the grounds that (a) if the code actually had such a
problem, valgrind testing would have found it, and (b) the message is
saying in so many words that they're ignoring our code in favor of
somebody's apparently-inaccurate model of said code.

			regards, tom lane






^ permalink  raw  reply  [nested|flat] 23+ messages in thread

end of thread, other threads:[~2025-02-13 19:05 UTC | newest]

Thread overview: 23+ messages (download: mbox mbox.gz follow: Atom feed)
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2021-01-22 20:59 [PATCH v3 3/3] Fix sizing of tape read buffers. Heikki Linnakangas <[email protected]>
2021-01-22 20:59 [PATCH v3 3/3] Fix sizing of tape read buffers. Heikki Linnakangas <[email protected]>
2021-01-22 20:59 [PATCH v3 3/3] Fix sizing of tape read buffers. Heikki Linnakangas <[email protected]>
2021-01-22 20:59 [PATCH v3 3/3] Fix sizing of tape read buffers. Heikki Linnakangas <[email protected]>
2021-01-22 20:59 [PATCH v3 3/3] Fix sizing of tape read buffers. Heikki Linnakangas <[email protected]>
2021-01-22 20:59 [PATCH v3 3/3] Fix sizing of tape read buffers. Heikki Linnakangas <[email protected]>
2021-01-22 20:59 [PATCH v3 3/3] Fix sizing of tape read buffers. Heikki Linnakangas <[email protected]>
2021-01-22 20:59 [PATCH v3 3/3] Fix sizing of tape read buffers. Heikki Linnakangas <[email protected]>
2021-01-22 20:59 [PATCH v3 3/3] Fix sizing of tape read buffers. Heikki Linnakangas <[email protected]>
2021-01-22 20:59 [PATCH v3 3/3] Fix sizing of tape read buffers. Heikki Linnakangas <[email protected]>
2021-01-22 20:59 [PATCH v3 3/3] Fix sizing of tape read buffers. Heikki Linnakangas <[email protected]>
2021-01-22 20:59 [PATCH v3 3/3] Fix sizing of tape read buffers. Heikki Linnakangas <[email protected]>
2021-01-22 20:59 [PATCH v3 3/3] Fix sizing of tape read buffers. Heikki Linnakangas <[email protected]>
2021-01-22 20:59 [PATCH v3 3/3] Fix sizing of tape read buffers. Heikki Linnakangas <[email protected]>
2021-01-22 20:59 [PATCH v3 3/3] Fix sizing of tape read buffers. Heikki Linnakangas <[email protected]>
2021-01-22 20:59 [PATCH v3 3/3] Fix sizing of tape read buffers. Heikki Linnakangas <[email protected]>
2021-01-22 20:59 [PATCH v3 3/3] Fix sizing of tape read buffers. Heikki Linnakangas <[email protected]>
2021-01-22 20:59 [PATCH v3 3/3] Fix sizing of tape read buffers. Heikki Linnakangas <[email protected]>
2021-01-22 20:59 [PATCH v3 3/3] Fix sizing of tape read buffers. Heikki Linnakangas <[email protected]>
2021-01-22 20:59 [PATCH v3 3/3] Fix sizing of tape read buffers. Heikki Linnakangas <[email protected]>
2021-01-22 20:59 [PATCH v3 3/3] Fix sizing of tape read buffers. Heikki Linnakangas <[email protected]>
2025-02-13 16:59 Re: pg17.3 PQescapeIdentifier() ignores len Ranier Vilela <[email protected]>
2025-02-13 19:05 ` Re: pg17.3 PQescapeIdentifier() ignores len Tom Lane <[email protected]>

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