Jan Wieck <janwi...@yahoo.com> writes: > Use this lmgr feature inside count_nondeletable_pages() of vacuumlazy.c to > periodically check, if there is a conflicting lock request waiting. If not, > keep going. If there is a waiter, truncate the relation to the point checked > thus far, release the AccessExclusiveLock, then loop back to where we > acquire this lock in the first place and continue checking/truncating.
I think that maybe we could just bail out after releasing the AccessExclusiveLock and trust autovacuum to get back to truncating that relation later. That would allow removing 2 of the 3 GUCs below: > autovacuum_truncate_lock_check = 100ms # how frequent to check > # for conflicting locks This is the one remaining. Could we maybe check for lock conflict after every move backward a page, or some multiple thereof? The goal would be to ensure that progress is made, while also being aware of concurrent activity, ala CHECK_FOR_INTERRUPTS(). Regards, -- Dimitri Fontaine http://2ndQuadrant.fr PostgreSQL : Expertise, Formation et Support -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
