On 1 July 2015 at 11:14, Andres Freund <and...@anarazel.de> wrote: > On 2015-07-01 09:08:11 +0100, Simon Riggs wrote: > > On 1 July 2015 at 09:00, Amit Kapila <amit.kapil...@gmail.com> wrote: > > > > > On Tue, Jun 30, 2015 at 12:32 PM, Simon Riggs <si...@2ndquadrant.com> > > > a. the semantics of new LWLock (CommitLock) introduced > > > by patch seems to be different in the sense that it is just taken in > > > Exclusive mode (and no Shared mode is required) as per your proposal. > We > > > could use existing LWLock APi's, but on the other hand we could even > > > invent new LWLock API for this kind of locking. > > > > > > > LWLock API code is already too complex, so -1 for more changes there > > I don't think that's a valid argument. It's better to have the > complexity in one place (lwlock) than have rather similar complexity in > several other places. The clog control lock is far from the only place > that would benefit from tricks along these lines. >
What "tricks" are being used?? Please explain why taking 2 locks is bad here, yet works fine elsewhere. -- Simon Riggs http://www.2ndQuadrant.com/ <http://www.2ndquadrant.com/> PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services
