Re: remove more archiving overhead

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.

[0] https://www.postgresql.org/message-id/20220407182954.GA1231544%40nathanxps13

--
Nathan Bossart
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