Message-ID: <768e6cb3-256d-9c0b-1797-62420ffca7ae@oss.nttdata.com>
Date: Thu, 7 Jul 2022 23:03:43 +0900
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Subject: Re: remove more archiving overhead
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To: Nathan Bossart <nathandbossart@gmail.com>,
 Kyotaro Horiguchi <horikyota.ntt@gmail.com>
Cc: pgsql-hackers@postgresql.org
References: <20220222011948.GA3850532@nathanxps13>
 <20220222173711.GA3852671@nathanxps13> <20220222195229.GA42988@nathanxps13>
 <20220224.141349.1809640551882183816.horikyota.ntt@gmail.com>
 <20220224175553.GA660690@nathanxps13> <20220407222327.GA1363808@nathanxps13>
From: Fujii Masao <masao.fujii@oss.nttdata.com>
In-Reply-To: <20220407222327.GA1363808@nathanxps13>
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On 2022/04/08 7:23, Nathan Bossart wrote:
> On Thu, Feb 24, 2022 at 09:55:53AM -0800, Nathan Bossart wrote:
>> Yes.  I found that a crash at an unfortunate moment can produce multiple
>> links to the same file in pg_wal, which seemed bad independent of archival.
>> By fixing that (i.e., switching from durable_rename_excl() to
>> durable_rename()), we not only avoid this problem, but we also avoid trying
>> to archive a file the server is concurrently writing.  Then, after a crash,
>> the WAL file to archive should either not exist (which is handled by the
>> archiver) or contain the same contents as any preexisting archives.
> 
> I moved the fix for this to a new thread [0] since I think it should be
> back-patched.  I've attached a new patch that only contains the part
> related to reducing archiving overhead.

Thanks for updating the patch. It looks good to me.
Barring any objection, I'm thinking to commit it.

Regards,

-- 
Fujii Masao
Advanced Computing Technology Center
Research and Development Headquarters
NTT DATA CORPORATION