Re: RecoveryWalAll and RecoveryWalStream wait events

Atsushi Torikoshi <atorik@gmail.com>

From: Atsushi Torikoshi <atorik@gmail.com>
To: Fujii Masao <masao.fujii@oss.nttdata.com>
Cc: Kyotaro Horiguchi <horikyota.ntt@gmail.com>, PostgreSQL-development <pgsql-hackers@postgresql.org>
Date: 2020-03-14T15:06:12Z
Lists: pgsql-hackers
On 2020/02/19 21:46 Fujii Masao <masao.fujii@oss.nttdata.com>:
>> I agree to the former, I think RecoveryWalInterval works well enough.
>RecoveryWalInterval sounds confusing to me...

IMHO as a user, I prefer RecoveryRetrieveRetryInterval because
it's easy to understand this wait_event is related to the
parameter 'wal_retrieve_retry_interval'.

Also from the point of balance, the explanation of
RecoveryRetrieveRetryInterval is lengthy, but I
sometimes feel explanations of wait_events in the
manual are so simple that it's hard to understand
well.


>    Waiting when WAL data is not available from any kind of sources
>    (local, archive or stream) before trying again to retrieve WAL data,

I think 'local' means pg_wal here, but the comment on
WaitForWALToBecomeAvailable() says checking pg_wal in
standby mode is 'not documented', so I'm a little bit worried
that users may be confused.

Regards,
--
Torikoshi Atsushi

Commits

  1. Rename the recovery-related wait events.

  2. Correct the descriptions of recovery-related wait events in docs.