Save slot's restart_lsn when invalidated due to size

We put it aside as invalidated_at, which let us show "lost" in
pg_replication slot.  Prior to this change, the state value was reported
as NULL.

Backpatch to 13.

Author: Kyotaro Horiguchi <horikyota.ntt@gmail.com>
Reviewed-by: Álvaro Herrera <alvherre@alvh.no-ip.org>
Discussion: https://postgr.es/m/20200617.101707.1735599255100002667.horikyota.ntt@gmail.com
Discussion: https://postgr.es/m/20200407.120905.1507671100168805403.horikyota.ntt@gmail.com
This commit is contained in:
Alvaro Herrera 2020-06-24 14:15:17 -04:00
parent 368d7f3297
commit 0188bb8253
No known key found for this signature in database
GPG Key ID: 1C20ACB9D5C564AE
5 changed files with 16 additions and 3 deletions

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@ -1226,6 +1226,7 @@ restart:
(uint32) restart_lsn)));
SpinLockAcquire(&s->mutex);
s->data.invalidated_at = s->data.restart_lsn;
s->data.restart_lsn = InvalidXLogRecPtr;
SpinLockRelease(&s->mutex);
ReplicationSlotRelease();

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@ -283,6 +283,7 @@ pg_get_replication_slots(PG_FUNCTION_ARGS)
bool nulls[PG_GET_REPLICATION_SLOTS_COLS];
WALAvailability walstate;
XLogSegNo last_removed_seg;
XLogRecPtr targetLSN;
int i;
if (!slot->in_use)
@ -342,7 +343,15 @@ pg_get_replication_slots(PG_FUNCTION_ARGS)
else
nulls[i++] = true;
walstate = GetWALAvailability(slot_contents.data.restart_lsn);
/*
* Report availability from invalidated_at when the slot has been
* invalidated; otherwise slots would appear as invalid without any
* more clues as to what happened.
*/
targetLSN = XLogRecPtrIsInvalid(slot_contents.data.restart_lsn) ?
slot_contents.data.invalidated_at :
slot_contents.data.restart_lsn;
walstate = GetWALAvailability(targetLSN);
switch (walstate)
{

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@ -326,7 +326,7 @@ extern void ShutdownXLOG(int code, Datum arg);
extern void InitXLOGAccess(void);
extern void CreateCheckPoint(int flags);
extern bool CreateRestartPoint(int flags);
extern WALAvailability GetWALAvailability(XLogRecPtr restart_lsn);
extern WALAvailability GetWALAvailability(XLogRecPtr targetLSN);
extern XLogRecPtr CalculateMaxmumSafeLSN(void);
extern void XLogPutNextOid(Oid nextOid);
extern XLogRecPtr XLogRestorePoint(const char *rpName);

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@ -79,6 +79,9 @@ typedef struct ReplicationSlotPersistentData
/* oldest LSN that might be required by this replication slot */
XLogRecPtr restart_lsn;
/* restart_lsn is copied here when the slot is invalidated */
XLogRecPtr invalidated_at;
/*
* Oldest LSN that the client has acked receipt for. This is used as the
* start_lsn point in case the client doesn't specify one, and also as a

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@ -186,7 +186,7 @@ ok( find_in_log(
$result = $node_master->safe_psql('postgres',
"SELECT slot_name, active, restart_lsn IS NULL, wal_status, min_safe_lsn FROM pg_replication_slots WHERE slot_name = 'rep1'"
);
is($result, "rep1|f|t||", 'check that the slot became inactive');
is($result, "rep1|f|t|lost|", 'check that the slot became inactive');
# The standby no longer can connect to the master
$logstart = get_log_size($node_standby);