diff options
Diffstat (limited to 'src/backend/access/spgist/spgutils.c')
| -rw-r--r-- | src/backend/access/spgist/spgutils.c | 18 |
1 files changed, 14 insertions, 4 deletions
diff --git a/src/backend/access/spgist/spgutils.c b/src/backend/access/spgist/spgutils.c index 3f793125f74..76b80146ff0 100644 --- a/src/backend/access/spgist/spgutils.c +++ b/src/backend/access/spgist/spgutils.c @@ -358,8 +358,19 @@ initSpGistState(SpGistState *state, Relation index) /* Make workspace for constructing dead tuples */ state->deadTupleStorage = palloc0(SGDTSIZE); - /* Set XID to use in redirection tuples */ - state->myXid = GetTopTransactionIdIfAny(); + /* + * Set horizon XID to use in redirection tuples. Use our own XID if we + * have one, else use InvalidTransactionId. The latter case can happen in + * VACUUM or REINDEX CONCURRENTLY, and in neither case would it be okay to + * force an XID to be assigned. VACUUM won't create any redirection + * tuples anyway, but REINDEX CONCURRENTLY can. Fortunately, REINDEX + * CONCURRENTLY doesn't mark the index valid until the end, so there could + * never be any concurrent scans "in flight" to a redirection tuple it has + * inserted. And it locks out VACUUM until the end, too. So it's okay + * for VACUUM to immediately expire a redirection tuple that contains an + * invalid xid. + */ + state->redirectXid = GetTopTransactionIdIfAny(); /* Assume we're not in an index build (spgbuild will override) */ state->isBuild = false; @@ -1075,8 +1086,7 @@ spgFormDeadTuple(SpGistState *state, int tupstate, if (tupstate == SPGIST_REDIRECT) { ItemPointerSet(&tuple->pointer, blkno, offnum); - Assert(TransactionIdIsValid(state->myXid)); - tuple->xid = state->myXid; + tuple->xid = state->redirectXid; } else { |