Re: Log connection establishment timings

On 2025/02/26 6:36, Melanie Plageman wrote:
> On Tue, Feb 25, 2025 at 3:23 PM Melanie Plageman
> <melanieplageman(at)gmail(dot)com> wrote:
>>
>> Thanks for doing this! I have implemented your suggestion in attached v3.
>
> I missed an include in the EXEC_BACKEND not defined case. attached v4
> is fixed up.

Thanks for updating the patch!

+ /* Capture time Postmaster initiates fork for logging */
+ if (child_type == B_BACKEND)
+ INSTR_TIME_SET_CURRENT(((BackendStartupData *) startup_data)->fork_time);

When log_connections is enabled, walsender connections are also logged.
However, with the patch, it seems the connection time for walsenders isn't captured.
Is this intentional?

With the current patch, when log_connections is enabled, the connection time is always
captured, and which might introduce performance overhead. No? Some users who enable
log_connections may not want this extra detail and want to avoid such overhead.
So, would it make sense to extend log_connections with a new option like "timing" and
log the connection time only when "timing" is specified?

+ ereport(LOG,
+ errmsg("backend ready for query. pid=%d. socket=%d. connection establishment times (ms): total: %ld, fork: %ld, authentication: %ld",
+ MyProcPid,
+ (int) MyClientSocket->sock,

Why expose the socket's file descriptor? I'm not sure how users would use that information.

Including the PID seems unnecessary since it's already available via log_line_prefix with %p?

Regards,

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