Horton

Re: Use standard SIGHUP and SIGTERM handlers in autoprewarm module

Fujii Masao <masao.fujii@oss.nttdata.com>

View thread View on postgr.es
From: Fujii Masao <masao.fujii@oss.nttdata.com>
To: Bharath Rupireddy <bharath.rupireddyforpostgres@gmail.com>
Cc: Craig Ringer <craig.ringer@enterprisedb.com>, PostgreSQL-development <pgsql-hackers@postgresql.org>, Robert Haas <robert.haas@enterprisedb.com>
Date: 2020-11-26T15:23:23Z
Lists: pgsql-hackers 

On 2020/11/27 0:15, Bharath Rupireddy wrote:
> On Thu, Nov 26, 2020 at 7:37 PM Fujii Masao <masao.fujii@oss.nttdata.com> wrote:
>>
>>> What do you mean by normal shutdown of bgworker? Is it that bgworker has exited successfully with exit code 0 or for some reason with exit code other than 0? Or is it when the postmaster is shutdown normally?
>>>
>>> IIUC, when a bgworker exists either normally with an exit code 0 or other than 0, then CleanupBackgroundWorker() is called in postmaster, a message(like below) is prepared, and the LogChildExit() is called with either DEBUG1 or LOG level and for instance the message you specified gets printed "background worker ... exited with exit code 1". I have not seen a FATAL message similar to "background worker ... exited with exit code 1" at the normal shutdown.
>>>
>>> snprintf(namebuf, MAXPGPATH, _("background worker \"%s\""), rw->rw_worker.bgw_type);
>>>
>>> LogChildExit(EXIT_STATUS_0(exitstatus) ? DEBUG1 : LOG, namebuf, pid, exitstatus);
>>>
>>> Am I missing something?
>>>
>>> If my analysis is right, then for instance, when a logical replication launcher is exited, it logs "background worker "logical replication launcher" exited with exit code X" with either DEBUG1 or LOG level but not with FATAL level.
>>
>> Yes, it's not with FATAL level. But that message looks like that it's
>> reporting error message. This is why we sometimes received
>> the complaints (e.g., [1][2]) about that message.
>>
> 
> Oh. Should we do something about it now?

No. This is not directly related to the issue that we are discussing
as I told upthread. Of course, it's better to work on this if we can
easily fix it. But seems not... So please ignore this my comment.

Regards,

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

Commits

  1. Revert "Get rid of the dedicated latch for signaling the startup process".

  2. Improve log message about termination of background workers.

  3. Use standard SIGTERM signal handler die() in test_shm_mq worker.

  4. Use standard SIGHUP and SIGTERM signal handlers in worker_spi.

  5. Use standard SIGHUP and SIGTERM handlers in walreceiver.

  6. pg_prewarm: make autoprewarm leader use standard SIGHUP and SIGTERM handlers.

  7. Get rid of the dedicated latch for signaling the startup process.

  8. Use standard SIGHUP handler in syslogger.

  9. Use PostgresSigHupHandler in more places.

  10. Fix race condition with unprotected use of a latch pointer variable.

  11. Remove remnants of ImmediateInterruptOK handling.

  12. Introduce Streaming Replication.