Message-ID: <a1a7e2b7-8f33-4313-baff-42e92ec14fd3@oss.nttdata.com>
Date: Tue, 7 Jan 2025 02:04:20 +0900
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Subject: Re: Enhancing Memory Context Statistics Reporting
To: Rahila Syed <rahilasyed90@gmail.com>,
 torikoshia <torikoshia@oss.nttdata.com>
Cc: PostgreSQL-development <pgsql-hackers@postgresql.org>
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From: Fujii Masao <masao.fujii@oss.nttdata.com>
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On 2025/01/06 22:16, Rahila Syed wrote:
> PFA the patch with above updates.

Thanks for updating the patch! I like this feature.

I tested this feature and encountered two issues:

Issue 1: Error with pg_get_process_memory_contexts()
When I used pg_get_process_memory_contexts() on the PID of a backend process
that had just caused an error but hadn’t rolled back yet,
the following error occurred:

   Session 1 (PID=70011):
   =# begin;
   =# select 1/0;
   ERROR:  division by zero
   
   Session 2:
   =# select * from pg_get_process_memory_contexts(70011, false);
   
   Session 1 terminated with:
   ERROR:  ResourceOwnerEnlarge called after release started
   FATAL:  terminating connection because protocol synchronization was lost


Issue 2: Segmentation Fault
When I ran pg_get_process_memory_contexts() every 0.1 seconds using
\watch command while running "make -j 4 installcheck-world",
I encountered a segmentation fault:

   LOG:  client backend (PID 97975) was terminated by signal 11: Segmentation fault: 11
   DETAIL:  Failed process was running: select infinite_recurse();
   LOG:  terminating any other active server processes

Regards,

-- 
Fujii Masao
Advanced Computing Technology Center
Research and Development Headquarters
NTT DATA CORPORATION