diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/backend/commands/vacuumlazy.c | 31 |
1 files changed, 21 insertions, 10 deletions
diff --git a/src/backend/commands/vacuumlazy.c b/src/backend/commands/vacuumlazy.c index 6778c7d58fa..6688ab38565 100644 --- a/src/backend/commands/vacuumlazy.c +++ b/src/backend/commands/vacuumlazy.c @@ -178,7 +178,8 @@ lazy_vacuum_rel(Relation onerel, VacuumStmt *vacstmt, int usecs; double read_rate, write_rate; - bool scan_all; + bool scan_all; /* should we scan all pages? */ + bool scanned_all; /* did we actually scan all pages? */ TransactionId freezeTableLimit; BlockNumber new_rel_pages; double new_rel_tuples; @@ -226,6 +227,21 @@ lazy_vacuum_rel(Relation onerel, VacuumStmt *vacstmt, vac_close_indexes(nindexes, Irel, NoLock); /* + * Compute whether we actually scanned the whole relation. If we did, we + * can adjust relfrozenxid and relminmxid. + * + * NB: We need to check this before truncating the relation, because that + * will change ->rel_pages. + */ + if (vacrelstats->scanned_pages < vacrelstats->rel_pages) + { + Assert(!scan_all); + scanned_all = false; + } + else + scanned_all = true; + + /* * Optionally truncate the relation. * * Don't even think about it unless we have a shot at releasing a goodly @@ -254,8 +270,8 @@ lazy_vacuum_rel(Relation onerel, VacuumStmt *vacstmt, * is all-visible we'd definitely like to know that. But clamp the value * to be not more than what we're setting relpages to. * - * Also, don't change relfrozenxid if we skipped any pages, since then we - * don't know for certain that all tuples have a newer xmin. + * Also, don't change relfrozenxid/relminmxid if we skipped any pages, + * since then we don't know for certain that all tuples have a newer xmin. */ new_rel_pages = vacrelstats->rel_pages; new_rel_tuples = vacrelstats->new_rel_tuples; @@ -269,13 +285,8 @@ lazy_vacuum_rel(Relation onerel, VacuumStmt *vacstmt, if (new_rel_allvisible > new_rel_pages) new_rel_allvisible = new_rel_pages; - new_frozen_xid = FreezeLimit; - if (vacrelstats->scanned_pages < vacrelstats->rel_pages) - new_frozen_xid = InvalidTransactionId; - - new_min_multi = MultiXactCutoff; - if (vacrelstats->scanned_pages < vacrelstats->rel_pages) - new_min_multi = InvalidMultiXactId; + new_frozen_xid = scanned_all ? FreezeLimit : InvalidTransactionId; + new_min_multi = scanned_all ? MultiXactCutoff : InvalidMultiXactId; vac_update_relstats(onerel, new_rel_pages, |