From: | Julien Rouhaud <rjuju123(at)gmail(dot)com> |
---|---|
To: | Magnus Hagander <magnus(at)hagander(dot)net> |
Cc: | Michael Paquier <michael(at)paquier(dot)xyz>, David Steele <david(at)pgmasters(dot)net>, Tomas Vondra <tomas(dot)vondra(at)2ndquadrant(dot)com>, Robert Haas <robertmhaas(at)gmail(dot)com>, PostgreSQL-development <pgsql-hackers(at)postgresql(dot)org> |
Subject: | Re: Checksum errors in pg_stat_database |
Date: | 2019-04-04 12:53:55 |
Message-ID: | CAOBaU_bVsG6RdiitbkbPEwJsTr1b1JetyuvVh3m0j-7sg8U9kg@mail.gmail.com |
Views: | Raw Message | Whole Thread | Download mbox | Resend email |
Thread: | |
Lists: | pgsql-hackers |
On Thu, Apr 4, 2019 at 1:25 PM Magnus Hagander <magnus(at)hagander(dot)net> wrote:
>
> On Thu, Apr 4, 2019 at 10:47 AM Julien Rouhaud <rjuju123(at)gmail(dot)com> wrote:
>>
>> Actually we do track counters for shared relations (see
>> pgstat_report_stat), we just don't expose them in any view. But it's
>> still possible to get the counters manually:
>>
>> # select pg_stat_get_db_blocks_hit(0);
>> pg_stat_get_db_blocks_hit
>> ---------------------------
>> 2710329
>> (1 row)
>
>
> Oh, right, we do actually collect it, we just don't show is. So that's another argument *for* having it in pg_stat_database. Or at least not for having it in a checksum specific view, because then we should really make a separate view for this as well.
Ok, so let's expose all the shared counters in pg_stat_database and
remove the pg_stat_checksum view.
>> My main concern is that pg_stat_get_db_numbackends(0) report something
>> like the total number of backend (though it seems that there's an
>> extra connection accounted for, I don't know which process it's), so
>> if we expose it in pg_stat_database, sum(numbackends) won't make sense
>> anymore.
>
> We could also just hardcoded it so that one always shows 0?
That's a bit hacky, but that's probably the best compromise. Attached
v4 with all those changes.
Attachment | Content-Type | Size |
---|---|---|
pg_stat_checksums-v4.diff | text/x-patch | 11.4 KB |
From | Date | Subject | |
---|---|---|---|
Next Message | Alvaro Herrera | 2019-04-04 13:02:58 | Re: Refactoring the checkpointer's fsync request queue |
Previous Message | Kyotaro HORIGUCHI | 2019-04-04 12:52:55 | Re: Protect syscache from bloating with negative cache entries |