pgsql: Skip WAL recycling and preallocation during archive recovery.

Skip WAL recycling and preallocation during archive recovery.

The previous commit addressed the chief consequences of a race condition
between InstallXLogFileSegment() and KeepFileRestoredFromArchive().  Fix
three lesser consequences.  A spurious durable_rename_excl() LOG message
remained possible.  KeepFileRestoredFromArchive() wasted the proceeds of
WAL recycling and preallocation.  Finally, XLogFileInitInternal() could
return a descriptor for a file that KeepFileRestoredFromArchive() had
already unlinked.  That felt like a recipe for future bugs.

Discussion: https://postgr.es/m/20210202151416.GB3304930@rfd.leadboat.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/cc2c7d65fc27e877c9f407587b0b92d46cd6dd16

Modified Files
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src/backend/access/transam/xlog.c | 65 ++++++++++++++++++++++++++++++++++-----
1 file changed, 57 insertions(+), 8 deletions(-)