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Message-ID: <7c857e55-de24-4b3b-ba7b-7116648119ac@aklaver.com>
Date: Thu, 29 Jan 2026 16:14:28 -0800
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Subject: Re: What happens if the socket lock file is deleted?
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: "stevej@stevej.name" <stevej@stevej.name>,
 pgsql-general@lists.postgresql.org
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 <1363739.1769721879@sss.pgh.pa.us>
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From: Adrian Klaver <adrian.klaver@aklaver.com>
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On 1/29/26 13:24, Tom Lane wrote:
> Adrian Klaver <adrian.klaver@aklaver.com> writes:
>>   From here at ~line 1781:
> 
>> https://github.com/postgres/postgres/blob/master/src/backend/postmaster/postmaster.c
> 
>>          /*
>>           * Once a minute, verify that postmaster.pid hasn't been removed or
>>           * overwritten.  If it has, we force a shutdown.
> 
> Actually, Steve was asking about socket lock files, so the relevant
> code fragment is the bit just below that:

Aah, I was close but no cigar.

Well at least I learned something.

> 
>          /*
>           * Touch Unix socket and lock files every 58 minutes, to ensure that
>           * they are not removed by overzealous /tmp-cleaning tasks.  We assume
>           * no one runs cleaners with cutoff times of less than an hour ...
>           */
>          if (now - last_touch_time >= 58 * SECS_PER_MINUTE)
>          {
>              TouchSocketFiles();
>              TouchSocketLockFiles();
>              last_touch_time = now;
>          }
> 
> 			regards, tom lane


-- 
Adrian Klaver
adrian.klaver@aklaver.com