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Fix data loss at inplace update after heap_update().

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As previously-added tests demonstrated, heap_inplace_update() could
instead update an unrelated tuple of the same catalog.  It could lose
the update.  Losing relhasindex=t was a source of index corruption.
Inplace-updating commands like VACUUM will now wait for heap_update()
commands like GRANT TABLE and GRANT DATABASE.  That isn't ideal, but a
long-running GRANT already hurts VACUUM progress more just by keeping an
XID running.  The VACUUM will behave like a DELETE or UPDATE waiting for
the uncommitted change.

For implementation details, start at the systable_inplace_update_begin()
header comment and README.tuplock.  Back-patch to v12 (all supported
versions).  In back branches, retain a deprecated heap_inplace_update(),
for extensions.

Reported by Smolkin Grigory.  Reviewed by Nitin Motiani, (in earlier
versions) Heikki Linnakangas, and (in earlier versions) Alexander
Lakhin.

Discussion: https://postgr.es/m/CAMp+ueZQz3yDk7qg42hk6-9gxniYbp-=bG2mgqecErqR5gGGOA@mail.gmail.com
This commit is contained in:
Noah Misch
2024-09-24 15:25:18 -07:00
parent dbf3f974ee
commit a07e03fd8f
16 changed files with 801 additions and 155 deletions
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9
src/include/access/genam.h
View File

@ -233,5 +233,14 @@ extern SysScanDesc systable_beginscan_ordered(Relation heapRelation,
extern HeapTuple systable_getnext_ordered(SysScanDesc sysscan,
ScanDirection direction);
extern void systable_endscan_ordered(SysScanDesc sysscan);
extern void systable_inplace_update_begin(Relation relation,
Oid indexId,
bool indexOK,
Snapshot snapshot,
int nkeys, const ScanKeyData *key,
HeapTuple *oldtupcopy,
void **state);
extern void systable_inplace_update_finish(void *state, HeapTuple tuple);
extern void systable_inplace_update_cancel(void *state);
#endif /* GENAM_H */

8
src/include/access/heapam.h
View File

@ -337,7 +337,13 @@ extern TM_Result heap_lock_tuple(Relation relation, HeapTuple tuple,
bool follow_updates,
Buffer *buffer, struct TM_FailureData *tmfd);
extern void heap_inplace_update(Relation relation, HeapTuple tuple);
extern bool heap_inplace_lock(Relation relation,
HeapTuple oldtup_ptr, Buffer buffer);
extern void heap_inplace_update_and_unlock(Relation relation,
HeapTuple oldtup, HeapTuple tuple,
Buffer buffer);
extern void heap_inplace_unlock(Relation relation,
HeapTuple oldtup, Buffer buffer);
extern bool heap_prepare_freeze_tuple(HeapTupleHeader tuple,
const struct VacuumCutoffs *cutoffs,
HeapPageFreeze *pagefrz,