Date: Sat, 31 Jul 2021 12:10:44 -0400
From: Alvaro Herrera <alvherre@alvh.no-ip.org>
To: "Bossart, Nathan" <bossartn@amazon.com>
Cc: Kyotaro Horiguchi <horikyota.ntt@gmail.com>,
	"x4mmm@yandex-team.ru" <x4mmm@yandex-team.ru>,
	"a.lubennikova@postgrespro.ru" <a.lubennikova@postgrespro.ru>,
	"hlinnaka@iki.fi" <hlinnaka@iki.fi>,
	"matsumura.ryo@fujitsu.com" <matsumura.ryo@fujitsu.com>,
	"masao.fujii@gmail.com" <masao.fujii@gmail.com>,
	"pgsql-hackers@postgresql.org" <pgsql-hackers@postgresql.org>
Subject: Re: archive status ".ready" files may be created too early
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On 2021-Jul-31, Bossart, Nathan wrote:

> On 7/30/21, 4:52 PM, "Alvaro Herrera" <alvherre@alvh.no-ip.org> wrote:

> > I noticed that XLogCtl->lastNotifiedSeg is protected by both the
> > info_lck and ArchNotifyLock.  I think it it's going to be protected by
> > the lwlock, then we should drop the use of the spinlock.
> 
> That seems reasonable to me.  This means that the lock is acquired at
> the end of every XLogWrite(),

Uhh, actually that there sounds really bad; it's going to be a serious
contention point.

Another option might be to make it an atomic.

-- 
Álvaro Herrera         PostgreSQL Developer  —  https://www.EnterpriseDB.com/