diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 9492a3c6b9..e834b923e4 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -24781,6 +24781,33 @@ SELECT collation for ('foo' COLLATE "de_DE");
+
+
+
+ pg_print_backend_memory_contexts
+
+ pg_print_backend_memory_contexts (
+ pid integer,
+ max_children integer )
+ boolean
+
+
+ Prints the memory contexts whose backend process has the specified
+ process ID.
+ max_children limits the max number of children
+ to print per one parent context.
+ Note that when multiple
+ pg_print_backend_memory_contexts called in
+ succession or simultaneously, max_children can
+ be the one of another
+ pg_print_backend_memory_contexts.
+ Backtrace will be printed based on the log configuration set. See
+ for more information.
+ Only superusers can call this function even when the specified process
+ is non-superuser backend.
+
+
+
diff --git a/src/backend/storage/ipc/ipci.c b/src/backend/storage/ipc/ipci.c
index 3e4ec53a97..785374719f 100644
--- a/src/backend/storage/ipc/ipci.c
+++ b/src/backend/storage/ipc/ipci.c
@@ -46,6 +46,7 @@
#include "storage/sinvaladt.h"
#include "storage/spin.h"
#include "utils/snapmgr.h"
+#include "utils/memutils.h"
/* GUCs */
int shared_memory_type = DEFAULT_SHARED_MEMORY_TYPE;
@@ -269,6 +270,7 @@ CreateSharedMemoryAndSemaphores(void)
BTreeShmemInit();
SyncScanShmemInit();
AsyncShmemInit();
+ McxtPrintShmemInit();
#ifdef EXEC_BACKEND
diff --git a/src/backend/storage/ipc/procsignal.c b/src/backend/storage/ipc/procsignal.c
index c6a8d4611e..dabb2025b1 100644
--- a/src/backend/storage/ipc/procsignal.c
+++ b/src/backend/storage/ipc/procsignal.c
@@ -30,6 +30,7 @@
#include "storage/shmem.h"
#include "storage/sinval.h"
#include "tcop/tcopprot.h"
+#include "utils/memutils.h"
/*
* The SIGUSR1 signal is multiplexed to support signaling multiple event
@@ -440,6 +441,20 @@ HandleProcSignalBarrierInterrupt(void)
/* latch will be set by procsignal_sigusr1_handler */
}
+/*
+ * HandleProcSignalPrintMemoryContext
+ *
+ * Handle receipt of an interrupt indicating print memory context.
+ * Signal handler portion of interrupt handling.
+ */
+static void
+HandleProcSignalPrintMemoryContext(void)
+{
+ InterruptPending = true;
+ PrintMemoryContextPending = true;
+ /* latch will be set by procsignal_sigusr1_handler */
+}
+
/*
* Perform global barrier related interrupt checking.
*
@@ -580,6 +595,29 @@ ProcessProcSignalBarrier(void)
ConditionVariableBroadcast(&MyProcSignalSlot->pss_barrierCV);
}
+/*
+ * ProcessPrintMemoryContextInterrupt
+ * The portion of print memory context interrupt handling that runs
+ * outside of the signal handler.
+ */
+void
+ProcessPrintMemoryContextInterrupt(void)
+{
+ int max_children;
+
+ PrintMemoryContextPending = false;
+
+ LWLockAcquire(McxtPrintLock, LW_SHARED);
+ max_children = *MaxChildrenPerContext;
+ LWLockRelease(McxtPrintLock);
+
+ ereport(LOG,
+ (errmsg("Printing memory contexts of PID %d. Max number of children per context is %d", MyProcPid, max_children)));
+
+ MemoryContextStatsDetail(TopMemoryContext, max_children, false);
+}
+
+
/*
* If it turns out that we couldn't absorb one or more barrier types, either
* because the barrier-processing functions returned false or due to an error,
@@ -675,6 +713,9 @@ procsignal_sigusr1_handler(SIGNAL_ARGS)
if (CheckProcSignal(PROCSIG_RECOVERY_CONFLICT_BUFFERPIN))
RecoveryConflictInterrupt(PROCSIG_RECOVERY_CONFLICT_BUFFERPIN);
+ if (CheckProcSignal(PROCSIG_PRINT_MEMORY_CONTEXT))
+ HandleProcSignalPrintMemoryContext();
+
SetLatch(MyLatch);
errno = save_errno;
diff --git a/src/backend/storage/lmgr/lwlocknames.txt b/src/backend/storage/lmgr/lwlocknames.txt
index 6c7cf6c295..f2aa1852b1 100644
--- a/src/backend/storage/lmgr/lwlocknames.txt
+++ b/src/backend/storage/lmgr/lwlocknames.txt
@@ -53,3 +53,4 @@ XactTruncationLock 44
# 45 was XactTruncationLock until removal of BackendRandomLock
WrapLimitsVacuumLock 46
NotifyQueueTailLock 47
+McxtPrintLock 48
diff --git a/src/backend/tcop/postgres.c b/src/backend/tcop/postgres.c
index 2b1b68109f..6fe47d1229 100644
--- a/src/backend/tcop/postgres.c
+++ b/src/backend/tcop/postgres.c
@@ -3295,6 +3295,9 @@ ProcessInterrupts(void)
if (ParallelMessagePending)
HandleParallelMessages();
+
+ if (PrintMemoryContextPending)
+ ProcessPrintMemoryContextInterrupt();
}
diff --git a/src/backend/utils/adt/mcxtfuncs.c b/src/backend/utils/adt/mcxtfuncs.c
index c02fa47550..07a95dd115 100644
--- a/src/backend/utils/adt/mcxtfuncs.c
+++ b/src/backend/utils/adt/mcxtfuncs.c
@@ -61,7 +61,7 @@ PutMemoryContextsStatsTupleStore(Tuplestorestate *tupstore,
/* Examine the context itself */
memset(&stat, 0, sizeof(stat));
- (*context->methods->stats) (context, NULL, (void *) &level, &stat);
+ (*context->methods->stats) (context, NULL, (void *) &level, &stat, true);
memset(values, 0, sizeof(values));
memset(nulls, 0, sizeof(nulls));
diff --git a/src/backend/utils/init/globals.c b/src/backend/utils/init/globals.c
index 73e0a672ae..32fe971386 100644
--- a/src/backend/utils/init/globals.c
+++ b/src/backend/utils/init/globals.c
@@ -34,6 +34,7 @@ volatile sig_atomic_t ClientConnectionLost = false;
volatile sig_atomic_t IdleInTransactionSessionTimeoutPending = false;
volatile sig_atomic_t IdleSessionTimeoutPending = false;
volatile sig_atomic_t ProcSignalBarrierPending = false;
+volatile sig_atomic_t PrintMemoryContextPending = false;
volatile uint32 InterruptHoldoffCount = 0;
volatile uint32 QueryCancelHoldoffCount = 0;
volatile uint32 CritSectionCount = 0;
diff --git a/src/backend/utils/mmgr/aset.c b/src/backend/utils/mmgr/aset.c
index ec6c130d0f..8e7fe09a0f 100644
--- a/src/backend/utils/mmgr/aset.c
+++ b/src/backend/utils/mmgr/aset.c
@@ -272,7 +272,8 @@ static Size AllocSetGetChunkSpace(MemoryContext context, void *pointer);
static bool AllocSetIsEmpty(MemoryContext context);
static void AllocSetStats(MemoryContext context,
MemoryStatsPrintFunc printfunc, void *passthru,
- MemoryContextCounters *totals);
+ MemoryContextCounters *totals,
+ bool is_dst_stderr);
#ifdef MEMORY_CONTEXT_CHECKING
static void AllocSetCheck(MemoryContext context);
@@ -1336,11 +1337,12 @@ AllocSetIsEmpty(MemoryContext context)
* printfunc: if not NULL, pass a human-readable stats string to this.
* passthru: pass this pointer through to printfunc.
* totals: if not NULL, add stats about this context into *totals.
+ * is_dst_stderr: is the output should be stderr or elog.
*/
static void
AllocSetStats(MemoryContext context,
MemoryStatsPrintFunc printfunc, void *passthru,
- MemoryContextCounters *totals)
+ MemoryContextCounters *totals, bool is_dst_stderr)
{
AllocSet set = (AllocSet) context;
Size nblocks = 0;
@@ -1379,7 +1381,7 @@ AllocSetStats(MemoryContext context,
"%zu total in %zd blocks; %zu free (%zd chunks); %zu used",
totalspace, nblocks, freespace, freechunks,
totalspace - freespace);
- printfunc(context, passthru, stats_string);
+ printfunc(context, passthru, stats_string, is_dst_stderr);
}
if (totals)
diff --git a/src/backend/utils/mmgr/generation.c b/src/backend/utils/mmgr/generation.c
index 2b90034764..b286308aa4 100644
--- a/src/backend/utils/mmgr/generation.c
+++ b/src/backend/utils/mmgr/generation.c
@@ -155,7 +155,8 @@ static Size GenerationGetChunkSpace(MemoryContext context, void *pointer);
static bool GenerationIsEmpty(MemoryContext context);
static void GenerationStats(MemoryContext context,
MemoryStatsPrintFunc printfunc, void *passthru,
- MemoryContextCounters *totals);
+ MemoryContextCounters *totals,
+ bool is_dst_stderr);
#ifdef MEMORY_CONTEXT_CHECKING
static void GenerationCheck(MemoryContext context);
@@ -665,6 +666,7 @@ GenerationIsEmpty(MemoryContext context)
* printfunc: if not NULL, pass a human-readable stats string to this.
* passthru: pass this pointer through to printfunc.
* totals: if not NULL, add stats about this context into *totals.
+ * is_dst_stderr: is the output should be stderr or elog.
*
* XXX freespace only accounts for empty space at the end of the block, not
* space of freed chunks (which is unknown).
@@ -672,7 +674,7 @@ GenerationIsEmpty(MemoryContext context)
static void
GenerationStats(MemoryContext context,
MemoryStatsPrintFunc printfunc, void *passthru,
- MemoryContextCounters *totals)
+ MemoryContextCounters *totals, bool is_dst_stderr)
{
GenerationContext *set = (GenerationContext *) context;
Size nblocks = 0;
@@ -704,7 +706,7 @@ GenerationStats(MemoryContext context,
"%zu total in %zd blocks (%zd chunks); %zu free (%zd chunks); %zu used",
totalspace, nblocks, nchunks, freespace,
nfreechunks, totalspace - freespace);
- printfunc(context, passthru, stats_string);
+ printfunc(context, passthru, stats_string, is_dst_stderr);
}
if (totals)
diff --git a/src/backend/utils/mmgr/mcxt.c b/src/backend/utils/mmgr/mcxt.c
index 84472b9158..5389cf4507 100644
--- a/src/backend/utils/mmgr/mcxt.c
+++ b/src/backend/utils/mmgr/mcxt.c
@@ -23,6 +23,10 @@
#include "mb/pg_wchar.h"
#include "miscadmin.h"
+#include "storage/proc.h"
+#include "storage/procarray.h"
+#include "storage/procsignal.h"
+#include "utils/fmgrprotos.h"
#include "utils/memdebug.h"
#include "utils/memutils.h"
@@ -37,6 +41,12 @@
*/
MemoryContext CurrentMemoryContext = NULL;
+/*
+ * MaxChildrenPerContext
+ * Max number of children to print per one parent context.
+ */
+int *MaxChildrenPerContext = NULL;
+
/*
* Standard top-level contexts. For a description of the purpose of each
* of these contexts, refer to src/backend/utils/mmgr/README
@@ -55,9 +65,11 @@ MemoryContext PortalContext = NULL;
static void MemoryContextCallResetCallbacks(MemoryContext context);
static void MemoryContextStatsInternal(MemoryContext context, int level,
bool print, int max_children,
- MemoryContextCounters *totals);
+ MemoryContextCounters *totals,
+ bool is_dst_stderr);
static void MemoryContextStatsPrint(MemoryContext context, void *passthru,
- const char *stats_string);
+ const char *stats_string,
+ bool is_dst_stderr);
/*
* You should not do memory allocations within a critical section, because
@@ -487,6 +499,89 @@ MemoryContextMemAllocated(MemoryContext context, bool recurse)
return total;
}
+/*
+ * McxtPrintShmemInit
+ * Initialize shared memory area
+ */
+void
+McxtPrintShmemInit(void)
+{
+ bool found;
+
+ MaxChildrenPerContext = (int *)
+ ShmemInitStruct("Max number of children per context",
+ sizeof(int),
+ &found);
+ if (!found)
+ {
+ *MaxChildrenPerContext = 0;
+ }
+}
+
+/*
+ * pg_print_backend_memory_contexts
+ * Print memory contexts of the specified backend process.
+ */
+Datum
+pg_print_backend_memory_contexts(PG_FUNCTION_ARGS)
+{
+ int pid = PG_GETARG_INT32(0);
+ int max_children = PG_GETARG_INT32(1);
+
+ PGPROC *proc = BackendPidGetProc(pid);
+
+ if(max_children <= 0)
+ {
+ ereport(WARNING,
+ (errmsg("%d is invalid value", max_children),
+ errhint("second parameter is the number of context and it must be set to a value greater than or equal to 1")));
+
+ PG_RETURN_BOOL(false);
+ }
+
+ /*
+ * Check whether the target process is PostgreSQL backend process.
+ */
+ if (proc == NULL)
+ {
+ /*
+ * According to the thread below, it might be better to
+ * change this message.
+ *
+ * https://www.postgresql.org/message-id/CALj2ACW7Rr-R7mBcBQiXWPp%3DJV5chajjTdudLiF5YcpW-BmHhg%40mail.gmail.com
+ *
+ * Until the conclusion of the discussion, output the same
+ * message as pg_cancel_backend().
+ */
+ ereport(WARNING,
+ (errmsg("PID %d is not a PostgreSQL server process", pid)));
+
+ PG_RETURN_BOOL(false);
+ }
+
+ /* Only allow superusers to print memory contexts. */
+ if (!superuser())
+ {
+ ereport(WARNING,
+ (errmsg("must be a superuser to print memory contexts")));
+ PG_RETURN_BOOL(false);
+ }
+
+ LWLockAcquire(McxtPrintLock, LW_EXCLUSIVE);
+ *MaxChildrenPerContext = max_children;
+ LWLockRelease(McxtPrintLock);
+
+ if(!SendProcSignal(pid, PROCSIG_PRINT_MEMORY_CONTEXT, InvalidBackendId))
+ PG_RETURN_BOOL(true);
+ else
+ {
+ ereport(WARNING,
+ (errmsg("failed to send signal: %m")));
+
+ PG_RETURN_BOOL(false);
+ }
+}
+
/*
* MemoryContextStats
* Print statistics about the named context and all its descendants.
@@ -499,7 +594,7 @@ void
MemoryContextStats(MemoryContext context)
{
/* A hard-wired limit on the number of children is usually good enough */
- MemoryContextStatsDetail(context, 100);
+ MemoryContextStatsDetail(context, 100, true);
}
/*
@@ -508,19 +603,28 @@ MemoryContextStats(MemoryContext context)
* Entry point for use if you want to vary the number of child contexts shown.
*/
void
-MemoryContextStatsDetail(MemoryContext context, int max_children)
+MemoryContextStatsDetail(MemoryContext context, int max_children, bool is_dst_stderr)
{
MemoryContextCounters grand_totals;
memset(&grand_totals, 0, sizeof(grand_totals));
- MemoryContextStatsInternal(context, 0, true, max_children, &grand_totals);
+ MemoryContextStatsInternal(context, 0, true, max_children, &grand_totals, is_dst_stderr);
- fprintf(stderr,
- "Grand total: %zu bytes in %zd blocks; %zu free (%zd chunks); %zu used\n",
- grand_totals.totalspace, grand_totals.nblocks,
- grand_totals.freespace, grand_totals.freechunks,
- grand_totals.totalspace - grand_totals.freespace);
+ if (is_dst_stderr)
+ fprintf(stderr,
+ "Grand total: %zu bytes in %zd blocks; %zu free (%zd chunks); %zu used\n",
+ grand_totals.totalspace, grand_totals.nblocks,
+ grand_totals.freespace, grand_totals.freechunks,
+ grand_totals.totalspace - grand_totals.freespace);
+ else
+ ereport(LOG_SERVER_ONLY,
+ (errhidestmt(true),
+ errhidecontext(true),
+ errmsg_internal("Grand total: %zu bytes in %zd blocks; %zu free (%zd chunks); %zu used",
+ grand_totals.totalspace, grand_totals.nblocks,
+ grand_totals.freespace, grand_totals.freechunks,
+ grand_totals.totalspace - grand_totals.freespace)));
}
/*
@@ -533,7 +637,8 @@ MemoryContextStatsDetail(MemoryContext context, int max_children)
static void
MemoryContextStatsInternal(MemoryContext context, int level,
bool print, int max_children,
- MemoryContextCounters *totals)
+ MemoryContextCounters *totals,
+ bool is_dst_stderr)
{
MemoryContextCounters local_totals;
MemoryContext child;
@@ -545,7 +650,7 @@ MemoryContextStatsInternal(MemoryContext context, int level,
context->methods->stats(context,
print ? MemoryContextStatsPrint : NULL,
(void *) &level,
- totals);
+ totals, is_dst_stderr);
/*
* Examine children. If there are more than max_children of them, we do
@@ -560,11 +665,13 @@ MemoryContextStatsInternal(MemoryContext context, int level,
if (ichild < max_children)
MemoryContextStatsInternal(child, level + 1,
print, max_children,
- totals);
+ totals,
+ is_dst_stderr);
else
MemoryContextStatsInternal(child, level + 1,
false, max_children,
- &local_totals);
+ &local_totals,
+ is_dst_stderr);
}
/* Deal with excess children */
@@ -574,16 +681,31 @@ MemoryContextStatsInternal(MemoryContext context, int level,
{
int i;
- for (i = 0; i <= level; i++)
- fprintf(stderr, " ");
- fprintf(stderr,
- "%d more child contexts containing %zu total in %zd blocks; %zu free (%zd chunks); %zu used\n",
- ichild - max_children,
- local_totals.totalspace,
- local_totals.nblocks,
- local_totals.freespace,
- local_totals.freechunks,
- local_totals.totalspace - local_totals.freespace);
+ if (is_dst_stderr)
+ {
+ for (i = 0; i <= level; i++)
+ fprintf(stderr, " ");
+ fprintf(stderr,
+ "%d more child contexts containing %zu total in %zd blocks; %zu free (%zd chunks); %zu used\n",
+ ichild - max_children,
+ local_totals.totalspace,
+ local_totals.nblocks,
+ local_totals.freespace,
+ local_totals.freechunks,
+ local_totals.totalspace - local_totals.freespace);
+ }
+ else
+ ereport(LOG_SERVER_ONLY,
+ (errhidestmt(true),
+ errhidecontext(true),
+ errmsg_internal("level: %d %d more child contexts containing %zu total in %zd blocks; %zu free (%zd chunks); %zu used",
+ level,
+ ichild - max_children,
+ local_totals.totalspace,
+ local_totals.nblocks,
+ local_totals.freespace,
+ local_totals.freechunks,
+ local_totals.totalspace - local_totals.freespace)));
}
if (totals)
@@ -605,12 +727,14 @@ MemoryContextStatsInternal(MemoryContext context, int level,
*/
static void
MemoryContextStatsPrint(MemoryContext context, void *passthru,
- const char *stats_string)
+ const char *stats_string,
+ bool is_dst_stderr)
{
int level = *(int *) passthru;
const char *name = context->name;
const char *ident = context->ident;
int i;
+ char truncated_ident[110];
/*
* It seems preferable to label dynahash contexts with just the hash table
@@ -623,11 +747,11 @@ MemoryContextStatsPrint(MemoryContext context, void *passthru,
ident = NULL;
}
- for (i = 0; i < level; i++)
- fprintf(stderr, " ");
- fprintf(stderr, "%s: %s", name, stats_string);
+ truncated_ident[0] = '\0';
+
if (ident)
{
+ char delimiter[] = ": ";
/*
* Some contexts may have very long identifiers (e.g., SQL queries).
* Arbitrarily truncate at 100 bytes, but be careful not to break
@@ -637,24 +761,42 @@ MemoryContextStatsPrint(MemoryContext context, void *passthru,
int idlen = strlen(ident);
bool truncated = false;
+ strcat(truncated_ident, delimiter);
+
if (idlen > 100)
{
idlen = pg_mbcliplen(ident, idlen, 100);
truncated = true;
}
- fprintf(stderr, ": ");
+
+ i = strlen(delimiter);
+
while (idlen-- > 0)
{
unsigned char c = *ident++;
if (c < ' ')
c = ' ';
- fputc(c, stderr);
+ truncated_ident[i++] = c;
}
+ truncated_ident[i] = '\0';
+
if (truncated)
- fprintf(stderr, "...");
+ strcat(truncated_ident, "...");
+ }
+
+ if (is_dst_stderr)
+ {
+ for (i = 0; i < level; i++)
+ fprintf(stderr, " ");
+ fprintf(stderr, "%s: %s%s\n", name, stats_string, truncated_ident);
}
- fputc('\n', stderr);
+ else
+ ereport(LOG_SERVER_ONLY,
+ (errhidestmt(true),
+ errhidecontext(true),
+ errmsg_internal("level: %d %s: %s%s",
+ level, name, stats_string, truncated_ident)));
}
/*
diff --git a/src/backend/utils/mmgr/slab.c b/src/backend/utils/mmgr/slab.c
index 9213be7c95..479b08bedd 100644
--- a/src/backend/utils/mmgr/slab.c
+++ b/src/backend/utils/mmgr/slab.c
@@ -135,7 +135,8 @@ static Size SlabGetChunkSpace(MemoryContext context, void *pointer);
static bool SlabIsEmpty(MemoryContext context);
static void SlabStats(MemoryContext context,
MemoryStatsPrintFunc printfunc, void *passthru,
- MemoryContextCounters *totals);
+ MemoryContextCounters *totals,
+ bool is_dst_stderr);
#ifdef MEMORY_CONTEXT_CHECKING
static void SlabCheck(MemoryContext context);
#endif
@@ -632,11 +633,13 @@ SlabIsEmpty(MemoryContext context)
* printfunc: if not NULL, pass a human-readable stats string to this.
* passthru: pass this pointer through to printfunc.
* totals: if not NULL, add stats about this context into *totals.
+ * is_dst_stderr: is the output should be stderr or elog.
*/
static void
SlabStats(MemoryContext context,
MemoryStatsPrintFunc printfunc, void *passthru,
- MemoryContextCounters *totals)
+ MemoryContextCounters *totals,
+ bool is_dst_stderr)
{
SlabContext *slab = castNode(SlabContext, context);
Size nblocks = 0;
@@ -671,7 +674,7 @@ SlabStats(MemoryContext context,
"%zu total in %zd blocks; %zu free (%zd chunks); %zu used",
totalspace, nblocks, freespace, freechunks,
totalspace - freespace);
- printfunc(context, passthru, stats_string);
+ printfunc(context, passthru, stats_string, is_dst_stderr);
}
if (totals)
diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat
index 93393fcfd4..ff6a9d2186 100644
--- a/src/include/catalog/pg_proc.dat
+++ b/src/include/catalog/pg_proc.dat
@@ -7917,6 +7917,12 @@
proargnames => '{name, ident, parent, level, total_bytes, total_nblocks, free_bytes, free_chunks, used_bytes}',
prosrc => 'pg_get_backend_memory_contexts' },
+# print memory context of specified backend
+{ oid => '4543', descr => 'print memory contexts of specified backend',
+ proname => 'pg_print_backend_memory_contexts',
+ provolatile => 'v', prorettype => 'bool',
+ proargtypes => 'int4 int4', prosrc => 'pg_print_backend_memory_contexts' },
+
# non-persistent series generator
{ oid => '1066', descr => 'non-persistent series generator',
proname => 'generate_series', prorows => '1000',
diff --git a/src/include/miscadmin.h b/src/include/miscadmin.h
index 013850ac28..711d6c2089 100644
--- a/src/include/miscadmin.h
+++ b/src/include/miscadmin.h
@@ -84,6 +84,7 @@ extern PGDLLIMPORT volatile sig_atomic_t ProcDiePending;
extern PGDLLIMPORT volatile sig_atomic_t IdleInTransactionSessionTimeoutPending;
extern PGDLLIMPORT volatile sig_atomic_t IdleSessionTimeoutPending;
extern PGDLLIMPORT volatile sig_atomic_t ProcSignalBarrierPending;
+extern PGDLLIMPORT volatile sig_atomic_t PrintMemoryContextPending;
extern PGDLLIMPORT volatile sig_atomic_t ClientConnectionLost;
diff --git a/src/include/nodes/memnodes.h b/src/include/nodes/memnodes.h
index 9331ef80fd..87a8501c37 100644
--- a/src/include/nodes/memnodes.h
+++ b/src/include/nodes/memnodes.h
@@ -52,7 +52,8 @@ typedef struct MemoryContextCounters
*/
typedef void (*MemoryStatsPrintFunc) (MemoryContext context, void *passthru,
- const char *stats_string);
+ const char *stats_string,
+ bool is_dst_stderr);
typedef struct MemoryContextMethods
{
@@ -66,7 +67,8 @@ typedef struct MemoryContextMethods
bool (*is_empty) (MemoryContext context);
void (*stats) (MemoryContext context,
MemoryStatsPrintFunc printfunc, void *passthru,
- MemoryContextCounters *totals);
+ MemoryContextCounters *totals,
+ bool is_dst_stderr);
#ifdef MEMORY_CONTEXT_CHECKING
void (*check) (MemoryContext context);
#endif
diff --git a/src/include/storage/procsignal.h b/src/include/storage/procsignal.h
index 4ae7dc33b8..0bfe290477 100644
--- a/src/include/storage/procsignal.h
+++ b/src/include/storage/procsignal.h
@@ -34,6 +34,8 @@ typedef enum
PROCSIG_PARALLEL_MESSAGE, /* message from cooperating parallel backend */
PROCSIG_WALSND_INIT_STOPPING, /* ask walsenders to prepare for shutdown */
PROCSIG_BARRIER, /* global barrier interrupt */
+ PROCSIG_PRINT_MEMORY_CONTEXT, /* ask specified backend to print the
+ memory context */
/* Recovery conflict reasons */
PROCSIG_RECOVERY_CONFLICT_DATABASE,
@@ -69,6 +71,7 @@ extern int SendProcSignal(pid_t pid, ProcSignalReason reason,
extern uint64 EmitProcSignalBarrier(ProcSignalBarrierType type);
extern void WaitForProcSignalBarrier(uint64 generation);
extern void ProcessProcSignalBarrier(void);
+extern void ProcessPrintMemoryContextInterrupt(void);
extern void procsignal_sigusr1_handler(SIGNAL_ARGS);
diff --git a/src/include/utils/memutils.h b/src/include/utils/memutils.h
index 36aae4e51c..db638c2f3f 100644
--- a/src/include/utils/memutils.h
+++ b/src/include/utils/memutils.h
@@ -63,6 +63,9 @@ extern PGDLLIMPORT MemoryContext CurTransactionContext;
/* This is a transient link to the active portal's memory context: */
extern PGDLLIMPORT MemoryContext PortalContext;
+
+extern int *MaxChildrenPerContext;
+
/* Backwards compatibility macro */
#define MemoryContextResetAndDeleteChildren(ctx) MemoryContextReset(ctx)
@@ -84,9 +87,11 @@ extern MemoryContext MemoryContextGetParent(MemoryContext context);
extern bool MemoryContextIsEmpty(MemoryContext context);
extern Size MemoryContextMemAllocated(MemoryContext context, bool recurse);
extern void MemoryContextStats(MemoryContext context);
-extern void MemoryContextStatsDetail(MemoryContext context, int max_children);
+extern void MemoryContextStatsDetail(MemoryContext context, int max_children,
+ bool is_dst_stderr);
extern void MemoryContextAllowInCriticalSection(MemoryContext context,
bool allow);
+extern void McxtPrintShmemInit(void);
#ifdef MEMORY_CONTEXT_CHECKING
extern void MemoryContextCheck(MemoryContext context);
diff --git a/src/test/modules/test_misc/t/002_print_memory_context_validation.pl b/src/test/modules/test_misc/t/002_print_memory_context_validation.pl
new file mode 100644
index 0000000000..61e318806f
--- /dev/null
+++ b/src/test/modules/test_misc/t/002_print_memory_context_validation.pl
@@ -0,0 +1,89 @@
+use strict;
+use warnings;
+use PostgresNode;
+use TestLib;
+use Test::More tests => 4;
+
+# Set up node with logging collector
+my $node = get_new_node('primary');
+$node->init();
+$node->append_conf(
+ 'postgresql.conf', qq{
+ logging_collector = on
+ lc_messages = 'C'
+ });
+
+$node->start();
+
+# Verify that log output gets to the file
+$node->psql('postgres', 'select pg_print_backend_memory_contexts(pg_backend_pid(), 100)');
+
+# might need to retry if logging collector process is slow...
+my $max_attempts = 180 * 10;
+
+my $current_logfiles;
+for (my $attempts = 0; $attempts < $max_attempts; $attempts++)
+{
+ eval {
+ $current_logfiles = slurp_file($node->data_dir . '/current_logfiles');
+ };
+ last unless $@;
+ usleep(100_000);
+}
+die $@ if $@;
+
+note "current_logfiles = $current_logfiles";
+
+like(
+ $current_logfiles,
+ qr|^stderr log/postgresql-.*log$|,
+ 'current_logfiles is sane');
+
+my $lfname = $current_logfiles;
+$lfname =~ s/^stderr //;
+chomp $lfname;
+
+my $logfile;
+my $print_count;
+
+# Verify that the backtraces of the processes are logged into logfile.
+for (my $attempts = 0; $attempts < $max_attempts; $attempts++)
+{
+ $logfile = $node->data_dir . '/' . $lfname;
+ chomp $logfile;
+ print "file is $logfile";
+ open my $fh, '<', $logfile
+ or die "Could not open '$logfile' $!";
+ while (my $line = <$fh>)
+ {
+ chomp $line;
+ if ($line =~ m/Grand total: \d+ bytes in \d+ blocks/)
+ {
+ $print_count++;
+ }
+ }
+ last if $print_count == 1;
+ usleep(100_000);
+}
+
+is($print_count, 1, 'found expected memory context print in the log file');
+
+my $output;
+
+$node->psql('postgres', 'select pg_print_backend_memory_contexts(pg_backend_pid(), 0)',
+ stderr => \$output);
+
+like(
+ $output,
+ qr/0 is invalid value/,
+ 'max_children must be set to a value greater than or equal to 1');
+
+$node->psql('postgres', 'select pg_print_backend_memory_contexts(1, 10)',
+ stderr => \$output);
+
+like(
+ $output,
+ qr/PID 1 is not a PostgreSQL server process/,
+ 'target PID is not PostgreSQL server process');
+
+$node->stop('fast');