diff options
Diffstat (limited to 'src/backend/access/nbtree/nbtsearch.c')
| -rw-r--r-- | src/backend/access/nbtree/nbtsearch.c | 11 |
1 files changed, 3 insertions, 8 deletions
diff --git a/src/backend/access/nbtree/nbtsearch.c b/src/backend/access/nbtree/nbtsearch.c index fdf0e5654a..598087612a 100644 --- a/src/backend/access/nbtree/nbtsearch.c +++ b/src/backend/access/nbtree/nbtsearch.c @@ -50,16 +50,11 @@ static inline void _bt_initialize_more_data(BTScanOpaque so, ScanDirection dir); /* * _bt_drop_lock_and_maybe_pin() * - * Unlock the buffer; and if it is safe to release the pin, do that, too. It - * is safe if the scan is using an MVCC snapshot and the index is WAL-logged. + * Unlock the buffer; and if it is safe to release the pin, do that, too. * This will prevent vacuum from stalling in a blocked state trying to read a - * page when a cursor is sitting on it -- at least in many important cases. + * page when a cursor is sitting on it. * - * Set the buffer to invalid if the pin is released, since the buffer may be - * re-used. If we need to go back to this block (for example, to apply - * LP_DEAD hints) we must get a fresh reference to the buffer. Hopefully it - * will remain in shared memory for as long as it takes to scan the index - * buffer page. + * See nbtree/README section on making concurrent TID recycling safe. */ static void _bt_drop_lock_and_maybe_pin(IndexScanDesc scan, BTScanPos sp) |