diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/backend/commands/vacuumlazy.c | 26 |
1 files changed, 17 insertions, 9 deletions
diff --git a/src/backend/commands/vacuumlazy.c b/src/backend/commands/vacuumlazy.c index b4abeed5ac9..5d6d031b481 100644 --- a/src/backend/commands/vacuumlazy.c +++ b/src/backend/commands/vacuumlazy.c @@ -1214,13 +1214,6 @@ lazy_vacuum_page(Relation onerel, BlockNumber blkno, Buffer buffer, PageRepairFragmentation(page); /* - * Now that we have removed the dead tuples from the page, once again - * check if the page has become all-visible. - */ - if (heap_page_is_all_visible(onerel, buffer, &visibility_cutoff_xid)) - PageSetAllVisible(page); - - /* * Mark buffer dirty before we write WAL. */ MarkBufferDirty(buffer); @@ -1238,6 +1231,23 @@ lazy_vacuum_page(Relation onerel, BlockNumber blkno, Buffer buffer, } /* + * End critical section, so we safely can do visibility tests (which + * possibly need to perform IO and allocate memory!). If we crash now the + * page (including the corresponding vm bit) might not be marked all + * visible, but that's fine. A later vacuum will fix that. + */ + END_CRIT_SECTION(); + + /* + * Now that we have removed the dead tuples from the page, once again + * check if the page has become all-visible. The page is already marked + * dirty, exclusively locked, and, if needed, a full page image has been + * emitted in the log_heap_clean() above. + */ + if (heap_page_is_all_visible(onerel, buffer, &visibility_cutoff_xid)) + PageSetAllVisible(page); + + /* * All the changes to the heap page have been done. If the all-visible * flag is now set, also set the VM bit. */ @@ -1249,8 +1259,6 @@ lazy_vacuum_page(Relation onerel, BlockNumber blkno, Buffer buffer, visibility_cutoff_xid); } - END_CRIT_SECTION(); - return tupindex; } |