Is there a known bug with SKIP LOCKED and "tuple to be locked was already moved to another partition due to concurrent update"?

2020-06-30 Thread Gunther Schadow
Hi all, long time ago I devised with your help a task queuing system which uses SELECT ... FOR UPDATE SKIP LOCKED for many parallel workers to find tasks in the queue, and it used a partitioned table where the hot part of the queue is short and so the query for a job is quick and the skip loc

Re: Recommended value for pg_test_fsync

2020-06-30 Thread Jeff Janes
On Tue, Jun 30, 2020 at 1:02 AM Nikhil Shetty wrote: > Hi Bruce, > > Based on pg_test_fsync results, should we choose open_datasync or > fdatasync as wal_sync_method? Can we rely on pg_test_fsync for choosing the > best wal_sync_method or is there any other way? > Probably the default of fdatasy

Re: Recommended value for pg_test_fsync

2020-06-30 Thread Jeff Janes
On Mon, Jun 29, 2020 at 5:27 AM Nikhil Shetty wrote: > Hi Team, > > We have a PostgreSQL 11.5.6 database running on VM. > RAM - 48GB > CPU - 6 cores > Disk - SSD on SAN > > We wanted to check how the WAL disk is performing using pg_test_fsync.We > ran a test and got around 870 ops/sec for opendat

Re: Recommended value for pg_test_fsync

2020-06-30 Thread Bruce Momjian
On Tue, Jun 30, 2020 at 10:32:13AM +0530, Nikhil Shetty wrote: > Hi Bruce, > > Based on pg_test_fsync results, should we choose open_datasync or fdatasync as > wal_sync_method? Can we rely on pg_test_fsync for choosing the best I would just pick the fastest method, but if the method is _too_ fast