On 2020-09-28 12:43, Amit Kapila wrote:
On Mon, Sep 28, 2020 at 8:24 AM Kyotaro Horiguchi
<horikyota....@gmail.com> wrote:
At Mon, 28 Sep 2020 08:11:23 +0530, Amit Kapila
<amit.kapil...@gmail.com> wrote in
> One other thing that occurred to me today is can't we keep this as
> part of PgStat_GlobalStats? We can use pg_stat_reset_shared('wal'); to
> reset it. It seems to me this is a cluster-wide stats and somewhat
> similar to some of the other stats we maintain there.
I like that direction, but PgStat_GlobalStats is actually
PgStat_BgWriterStats and cleard by a RESET_BGWRITER message.
Yeah, I think if we want to pursue this direction then we probably
need to have a separate message to set/reset WAL-related stuff. I
guess we probably need to have a separate reset timestamp for WAL. I
think the difference would be that we can have one structure to refer
to global_stats instead of referring to multiple structures and we
don't need to issue separate read/write calls but OTOH I don't see
many disadvantages of the current approach as well.
IIUC, if we keep wal stats as part of PgStat_GlobalStats,
don't we need to add PgStat_ArchiverStats and PgStat_SLRUStats
to PgStat_GlobalStats too?
Since this is refactoring, I think it's better to make another patch
after the current patch is merged.
Regards,
--
Masahiro Ikeda
NTT DATA CORPORATION
