Presently, archive status files are durably renamed from .ready to
.done to indicate that a file has been archived. Persisting this
rename to disk accounts for a significant amount of the overhead
associated with archiving. While durably renaming the file
prevents re-archiving in most cases, archive commands and libraries
must already gracefully handle attempts to re-archive the last
archived file after a crash (e.g., a crash immediately after
archive_command exits but before the server renames the status
file).
This change reduces the amount of overhead associated with
archiving by using rename() instead of durable_rename() to rename
the archive status files. As a consequence, the server is more
likely to attempt to re-archive files after a crash, but as noted
above, archive commands and modules are already expected to handle
this. It is also possible that the server will attempt to re-
archive files that have been removed or recycled, but the archiver
already handles this, too.
Author: Nathan Bossart
Reviewed-by: Kyotaro Horiguchi, Fujii Masao
Discussion: https://postgr.es/m/20220222011948.GA3850532@nathanxps13
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