Re: [HACKERS] Document that vacuum can't truncate if old_snapshot_threshold >= 0

2016-07-19 Thread Kevin Grittner
On Wed, Jul 13, 2016 at 4:14 PM, Andres Freund wrote: > Currently, if old_snapshot_threshold is enabled, vacuum is prevented > from truncating tables: > static bool > should_attempt_truncation(LVRelStats *vacrelstats) > { > BlockNumber possibly_freeable; > > possibly_freeable = va

[HACKERS] Document that vacuum can't truncate if old_snapshot_threshold >= 0

2016-07-13 Thread Andres Freund
Hi, Currently, if old_snapshot_threshold is enabled, vacuum is prevented from truncating tables: static bool should_attempt_truncation(LVRelStats *vacrelstats) { BlockNumber possibly_freeable; possibly_freeable = vacrelstats->rel_pages - vacrelstats->nonempty_pages; if (p