Re: More efficient truncation of pg_stat_activity query strings

Andres Freund <andres@anarazel.de>

From: Andres Freund <andres@anarazel.de>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Robert Haas <robertmhaas@gmail.com>, "pgsql-hackers@postgresql.org" <pgsql-hackers@postgresql.org>
Date: 2017-09-15T20:49:10Z
Lists: pgsql-hackers
On 2017-09-15 16:45:47 -0400, Tom Lane wrote:
> Andres Freund <andres@anarazel.de> writes:
> > Version correcting these is attached. Thanks!
> 
> I'd vote for undoing the s/st_activity/st_activity_raw/g business.
> That may have been useful while writing the patch, to ensure you
> found all the references; but it's just creating a lot of unnecessary
> delta in the final code, with the attendant hazards for back-patches.

I was wondering about that too (see [1]). My only concern is that some
extensions out there might be accessing the string expecting it to be
properly truncated. The rename at least forces them to look for the new
name...  I'm slightly in favor of keeping the rename, it doesn't seem
likely to cause a lot of backpatch pain.

Regards,

Andres Freund


[1] http://archives.postgresql.org/message-id/20170914060329.j7lt7oyyzquxiut6%40alap3.anarazel.de


Commits

  1. Speedup pgstat_report_activity by moving mb-aware truncation to read side.