RE: FW: query pg_stat_ssl hang 100%cpu

#0  ensure_record_cache_typmod_slot_exists (typmod=0) at typcache.c:1714
#1  0x000000000091185b in assign_record_type_typmod (tupDesc=<optimized out>, tupDesc@entry=0x27bc738) at
typcache.c:2001
#2  0x000000000091df03 in internal_get_result_type (funcid=<optimized out>, call_expr=<optimized out>,
rsinfo=<optimizedout>,
 
    resultTypeId=<optimized out>, resultTupleDesc=0x7ffc9dff8cd0) at funcapi.c:393
#3  0x000000000091e263 in get_expr_result_type (expr=expr@entry=0x2792798,
resultTypeId=resultTypeId@entry=0x7ffc9dff8ccc,
    resultTupleDesc=resultTupleDesc@entry=0x7ffc9dff8cd0) at funcapi.c:230
#4  0x00000000006a2fa5 in ExecInitFunctionScan (node=node@entry=0x273afa8, estate=estate@entry=0x269e948,
eflags=eflags@entry=16)at nodeFunctionscan.c:370
 
#5  0x000000000069084e in ExecInitNode (node=node@entry=0x273afa8, estate=estate@entry=0x269e948,
eflags=eflags@entry=16)at execProcnode.c:255
 
#6  0x000000000068a96d in InitPlan (eflags=16, queryDesc=0x273b2d8) at execMain.c:936
#7  standard_ExecutorStart (queryDesc=0x273b2d8, eflags=16) at execMain.c:263
#8  0x00007f67c2821d5d in pgss_ExecutorStart (queryDesc=0x273b2d8, eflags=<optimized out>) at pg_stat_statements.c:965
#9  0x00000000007fc226 in PortalStart (portal=portal@entry=0x26848b8, params=params@entry=0x0, eflags=eflags@entry=0,
snapshot=snapshot@entry=0x0)
    at pquery.c:514
#10 0x00000000007fa27f in exec_bind_message (input_message=0x7ffc9dff90d0) at postgres.c:1995
#11 PostgresMain (argc=argc@entry=1, argv=argv@entry=0x7ffc9dff9370, dbname=<optimized out>, username=<optimized out>)
atpostgres.c:4552
 
#12 0x000000000077a4ea in BackendRun (port=<optimized out>, port=<optimized out>) at postmaster.c:4537
#13 BackendStartup (port=<optimized out>) at postmaster.c:4259
#14 ServerLoop () at postmaster.c:1745
#15 0x000000000077b363 in PostmasterMain (argc=argc@entry=5, argv=argv@entry=0x256abc0) at postmaster.c:1417
#16 0x00000000004fec63 in main (argc=5, argv=0x256abc0) at main.c:209
(gdb) p RecordCacheArray
$1 = (TupleDesc *) 0x7f5fac365d90
(gdb) p RecordIdentifierArray
$2 = (uint64 *) 0x0

-----Original Message-----
From: Thomas Munro <thomas.munro@gmail.com> 
Sent: Thursday, September 7, 2023 6:36 PM
To: James Pang (chaolpan) <chaolpan@cisco.com>
Cc: Michael Paquier <michael@paquier.xyz>; PostgreSQL mailing lists <pgsql-bugs@lists.postgresql.org>
Subject: Re: FW: query pg_stat_ssl hang 100%cpu

On Thu, Sep 7, 2023 at 10:31 PM James Pang (chaolpan) <chaolpan@cisco.com> wrote:
>    Yes, checked the server history logs, we found when the backend starting hang there, operating system has out of
memorythat may lead to the allocation of RecordIdentierArray failed.
 

Can you please print out RecordCacheArray and RecordIdentifierArray?
For that theory, the first one must be non-NULL and the second one NULL.  That would lead to the infinite loop, I
think.