Make ycmdb.shared_archive runtime-changeable and add space saver (PG16) - #93
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Make ycmdb.shared_archive runtime-changeable and add space saver (PG16)#93x4m wants to merge 1 commit into
x4m wants to merge 1 commit into
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Change ycmdb.shared_archive from PGC_POSTMASTER to PGC_SIGHUP so the shared archive behavior can be toggled without a server restart. Add a new GUC ycmdb.shared_archive_space_saver (PGC_SIGHUP). When enabled on a standby it disables the shared-archive WAL retention: the walreceiver forces streamed segments to .done instead of holding them as .ready, and XLogArchiveCheckDone() lets checkpoint recycle such segments during recovery. This lets a disk-usage watcher relieve a standby that would otherwise accumulate unarchived WAL until it fills the disk and fails over (e.g. while the shared archive storage is unavailable). The trade-off is a gap in the archived WAL history; the flag has no effect on a primary. The new SharedArchiveRetentionActive() macro expresses "shared archive is active and retention is not overridden" and is used in the two retention decision points.
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Change ycmdb.shared_archive from PGC_POSTMASTER to PGC_SIGHUP so the shared archive behavior can be toggled without a server restart.
Add a new GUC ycmdb.shared_archive_space_saver (PGC_SIGHUP). When enabled on a standby it disables the shared-archive WAL retention: the walreceiver forces streamed segments to .done instead of holding them as .ready, and XLogArchiveCheckDone() lets checkpoint recycle such segments during recovery. This lets a disk-usage watcher relieve a standby that would otherwise accumulate unarchived WAL until it fills the disk and fails over (e.g. while the shared archive storage is unavailable). The trade-off is a gap in the archived WAL history; the flag has no effect on a primary.
The new SharedArchiveRetentionActive() macro expresses "shared archive is active and retention is not overridden" and is used in the two retention decision points.