diff options
Diffstat (limited to 'src/backend')
| -rw-r--r-- | src/backend/access/heap/vacuumlazy.c | 20 |
1 files changed, 7 insertions, 13 deletions
diff --git a/src/backend/access/heap/vacuumlazy.c b/src/backend/access/heap/vacuumlazy.c index 06fd15405f7..21bd104f69d 100644 --- a/src/backend/access/heap/vacuumlazy.c +++ b/src/backend/access/heap/vacuumlazy.c @@ -1788,13 +1788,13 @@ retry: if (tuples_frozen == 0) { /* - * We're freezing all eligible tuples on the page, but have no - * freeze plans to execute. This is structured as a case where - * the page is nominally frozen so that we set pages all-frozen - * whenever no freeze plans need to be executed to make it safe. - * If this was handled via "no freeze" processing instead then - * VACUUM would senselessly waste certain opportunities to set - * pages all-frozen (not just all-visible) at no added cost. + * We have no freeze plans to execute, so there's no added cost + * from following the freeze path. That's why it was chosen. + * This is important in the case where the page only contains + * totally frozen tuples at this point (perhaps only following + * pruning). Such pages can be marked all-frozen in the VM by our + * caller, even though none of its tuples were newly frozen here + * (note that the "no freeze" path never sets pages all-frozen). * * We never increment the frozen_pages instrumentation counter * here, since it only counts pages with newly frozen tuples @@ -1859,12 +1859,6 @@ retry: if (!heap_page_is_all_visible(vacrel, buf, &cutoff, &all_frozen)) Assert(false); - /* - * It's possible that we froze tuples and made the page's XID cutoff - * (for recovery conflict purposes) FrozenTransactionId. This is okay - * because visibility_cutoff_xid will be logged by our caller in a - * moment. - */ Assert(!TransactionIdIsValid(cutoff) || cutoff == prunestate->visibility_cutoff_xid); } |