On Sun, Apr 18, 2010 at 4:22 PM, Simon Riggs <si...@2ndquadrant.com> wrote: > On Sun, 2010-04-18 at 13:16 -0700, David Fetter wrote: >> On Sun, Apr 18, 2010 at 12:01:05PM +0100, Simon Riggs wrote: >> > On Sun, 2010-04-18 at 08:24 +0100, Simon Riggs wrote: >> > > On Sat, 2010-04-17 at 18:52 -0400, Tom Lane wrote: >> > > > Simon Riggs <si...@2ndquadrant.com> writes: >> > > > > What I'm not clear on is why you've used a spinlock everywhere >> > > > > when only weak-memory thang CPUs are a problem. Why not have a >> > > > > weak-memory-protect macro that does does nada when the >> > > > > hardware already protects us? (i.e. a spinlock only for the >> > > > > hardware that needs it). >> > > > >> > > > Well, we could certainly consider that, if we had enough places >> > > > where there was a demonstrable benefit from it. I couldn't >> > > > measure any real slowdown from adding a spinlock in that sinval >> > > > code, so I didn't propose doing so at the time --- and I'm >> > > > pretty dubious that this code is sufficiently >> > > > performance-critical to justify the work, either. >> > > >> > > OK, I'll put a spinlock around access to the head of the array. >> > >> > v2 patch attached >> >> If you've committed this, or any other patch you've sent here, >> *please* mention so on the same thread. > > I haven't yet. I've written two patches - this is a major module rewrite > and is still under discussion. The other patch has nothing to do with > this (though I did accidentally include a couple of changes from this > patch and immediately revoked them). > > I will wait awhile to see if anybody has some independent test results.
So, does anyone have a few cycles to test this out? We are down to handful of remaining open items, so getting this tested and committed sooner = beta sooner. ...Robert -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
