Boszormenyi Zoltan írta: > Marc Cousin írta: > >> The Thursday 29 July 2010 13:55:38, Boszormenyi Zoltan wrote : >> >> >>> I fixed this by adding CheckLockTimeout() function that works like >>> CheckStatementTimeout() and ensuring that the same start time is >>> used for both deadlock_timeout and lock_timeout if both are active. >>> The preference of errors if their timeout values are equal is: >>> statement_timeout > lock_timeout > deadlock_timeout >>> >>> >> As soon as lock_timeout is bigger than deadlock_timeout, it doesn't >> work, with this new version. >> >> Keeping the deadlock_timeout to 1s, when lock_timeout >= 1001, >> lock_timeout doesn't trigger anymore. >> >> > > I missed one case when the lock_timeout_active should have been set > but the timer must not have been re-set, this caused the problem. > I blame the hot weather and having no air conditioning. The second is > now fixed. :-) > > I also added one line in autovacuum.c to disable lock_timeout, > in case it's globally set in postgresq.conf as per Alvaro's comment. > > Also, I made sure that only one or two timeout causes (one of > deadlock_timeout > and lock_timeout in the first case or statement_timeout plus one of the > other two) > can be active at a time.
A little clarification is needed. The above statement is not entirely true. There can be a case when all three timeout causes can be active, but only when deadlock_timeout is the smallest of the three. If the fin_time value for the another timeout cause is smaller than for deadlock_timeout then there's no point to make deadlock_timeout active. And in case deadlock_timeout triggers and CheckDeadLock() finds that there really is a deadlock then the possibly active lock_timeout gets disabled to avoid calling RemoveFromWaitQueue() twice. I hope the comments in the code explain it well. > Previously I was able to trigger a segfault > with the default > 1sec deadlock_timeout and lock_timeout = 999 or 1001. Effectively, the > system's > clock resolution makes the lock_timeout and deadlock_timeout equal and > RemoveFromWaitQueue() was called twice. This way it's a lot more robust. > Best regards, Zoltán Böszörményi -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
