On Fri, Sep 20, 2024 at 07:00:00AM +0300, Alexander Lakhin wrote:
> I've found another two paths to reach that condition:
> CREATE INDEX CONCURRENTLY ON def (vec_quantizer(id, :'b'));
> ERROR: cannot fetch toast data without an active snapshot
>
> REINDEX INDEX CONCURRENTLY def_vec_quantizer_idx;
> (or REINDEX TABLE CONCURRENTLY def;)
> TRAP: failed Assert("HaveRegisteredOrActiveSnapshot()"), File:
> "toast_internals.c", Line: 668, PID: 2934502
Here's a (probably naive) attempt at fixing these, too. I'll give each
path a closer look once it feels like we've identified all the bugs.
> Perhaps it would make sense to check all CatalogTupleUpdate(pg_index, ...)
> calls (I've found 10 such instances, but haven't checked them yet).
Indeed.
--
nathan
>From b7432c42c0cea9c1aadba7c72f9ce2ba6e6407d2 Mon Sep 17 00:00:00 2001
From: Nathan Bossart <[email protected]>
Date: Fri, 20 Sep 2024 11:48:52 -0500
Subject: [PATCH v2 1/1] fix failed assertions due to pg_index's TOAST table
---
src/backend/catalog/index.c | 5 +++++
src/backend/commands/indexcmds.c | 9 +++++++++
2 files changed, 14 insertions(+)
diff --git a/src/backend/catalog/index.c b/src/backend/catalog/index.c
index b2b3ecb524..2e378ef4ef 100644
--- a/src/backend/catalog/index.c
+++ b/src/backend/catalog/index.c
@@ -2255,6 +2255,7 @@ index_drop(Oid indexId, bool concurrent, bool
concurrent_lock_mode)
PopActiveSnapshot();
CommitTransactionCommand();
StartTransactionCommand();
+ PushActiveSnapshot(GetTransactionSnapshot());
/*
* Now we must wait until no running transaction could be using
the
@@ -2283,8 +2284,10 @@ index_drop(Oid indexId, bool concurrent, bool
concurrent_lock_mode)
* Again, commit the transaction to make the pg_index update
visible
* to other sessions.
*/
+ PopActiveSnapshot();
CommitTransactionCommand();
StartTransactionCommand();
+ PushActiveSnapshot(GetTransactionSnapshot());
/*
* Wait till every transaction that saw the old index state has
@@ -2387,6 +2390,8 @@ index_drop(Oid indexId, bool concurrent, bool
concurrent_lock_mode)
{
UnlockRelationIdForSession(&heaprelid,
ShareUpdateExclusiveLock);
UnlockRelationIdForSession(&indexrelid,
ShareUpdateExclusiveLock);
+
+ PopActiveSnapshot();
}
}
diff --git a/src/backend/commands/indexcmds.c b/src/backend/commands/indexcmds.c
index f99c2d2dee..36318c81ea 100644
--- a/src/backend/commands/indexcmds.c
+++ b/src/backend/commands/indexcmds.c
@@ -1798,11 +1798,15 @@ DefineIndex(Oid tableId,
PROGRESS_CREATEIDX_PHASE_WAIT_3);
WaitForOlderSnapshots(limitXmin, true);
+ PushActiveSnapshot(GetTransactionSnapshot());
+
/*
* Index can now be marked valid -- update its pg_index entry
*/
index_set_state_flags(indexRelationId, INDEX_CREATE_SET_VALID);
+ PopActiveSnapshot();
+
/*
* The pg_index update will cause backends (including this one) to
update
* relcache entries for the index itself, but we should also send a
@@ -4236,6 +4240,8 @@ ReindexRelationConcurrently(const ReindexStmt *stmt, Oid
relationOid, const Rein
*/
set_indexsafe_procflags();
+ PushActiveSnapshot(GetTransactionSnapshot());
+
forboth(lc, indexIds, lc2, newIndexIds)
{
ReindexIndexInfo *oldidx = lfirst(lc);
@@ -4280,8 +4286,10 @@ ReindexRelationConcurrently(const ReindexStmt *stmt, Oid
relationOid, const Rein
}
/* Commit this transaction and make index swaps visible */
+ PopActiveSnapshot();
CommitTransactionCommand();
StartTransactionCommand();
+ PushActiveSnapshot(GetTransactionSnapshot());
/*
* While we could set PROC_IN_SAFE_IC if all indexes qualified, there's
no
@@ -4316,6 +4324,7 @@ ReindexRelationConcurrently(const ReindexStmt *stmt, Oid
relationOid, const Rein
}
/* Commit this transaction to make the updates visible. */
+ PopActiveSnapshot();
CommitTransactionCommand();
StartTransactionCommand();
--
2.39.5 (Apple Git-154)
