On Sun, Jun 1, 2014 at 1:05 PM, Andres Freund <and...@2ndquadrant.com> wrote: > On 2014-05-30 10:30:42 +0530, Amit Kapila wrote: > > On Wed, May 28, 2014 at 8:53 PM, Andres Freund <and...@2ndquadrant.com> > > > Since a64ca63e59c11d8fe6db24eee3d82b61db7c2c83 pg_sleep() uses > > > WaitLatch() to wait. That's fine in itself. But > > > procsignal_sigusr1_handler, which is used e.g. when resolving recovery > > > conflicts, doesn't unconditionally do a SetLatch(). > > > That means that we'll we'll currently not be able to cancel conflicting > > > backends during recovery for 10min. Now, I don't think that'll happen > > > too often in practice, but it's still annoying. > > > > How will such a situation occur, aren't we using pg_usleep during > > RecoveryConflict functions > > (ex. in ResolveRecoveryConflictWithVirtualXIDs)? > > I am not sure what you mean. pg_sleep() is the SQL callable function, a > different thing to pg_usleep().
I was not clear how such a situation can occur, but now looking at it bit more carefully, I think I understood that any backend calling pg_sleep() during recovery conflict resolution can face this situation. With Regards, Amit Kapila. EnterpriseDB: http://www.enterprisedb.com
