On 2016-02-04 18:21:41 +0530, Amit Kapila wrote: > I think generally it is good idea, but one thing worth a thought is that > by doing so, we need to acquire all WAL Insertion locks every > LOG_SNAPSHOT_INTERVAL_MS to check the last_insert_pos for > every slot, do you think it is matter of concern in any way for write > workloads or it won't effect as we need to do this periodically?
Michael and I just had an in-person discussion, and one of the topics was that. The plan was basically to adapt the patch to: 1) Store the progress lsn inside the wal insert lock 2) Change the HasActivity API to return an the last LSN at which there was activity, instead of a boolean. 2) Individually acquire each insert locks's lwlock to get it's progress LSN, but not the exclusive insert lock. We need the lwllock to avoid a torn 8byte read on some platforms. I think that mostly should address your concerns? Andres -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
