On Sat, Feb 15, 2014 at 11:17 AM, Andres Freund <and...@2ndquadrant.com> wrote: > On 2014-02-15 16:18:00 +0100, Andres Freund wrote: >> On 2014-02-15 10:06:41 -0500, Tom Lane wrote: >> > Andres Freund <and...@2ndquadrant.com> writes: >> > > My current conclusion is that backporting barriers.h is by far the most >> > > reasonable way to go. The compiler problems have been ironed out by >> > > now... >> > >> > -1. IMO that code is still quite unproven, and what's more, the >> > problem we're discussing here is completely hypothetical. If it >> > were real, we'd have field evidence of it. We've not had that >> > much trouble seeing instances of even very narrow race-condition >> > windows in the past. >> >> Well, the problem is that few of us have access to interesting !x86 >> machines to run tests, and that's where we'd see problems (since x86 >> gives enough guarantees to avoid this unless the compiler reorders >> stuff). I am personally fine with just using volatiles to avoid >> reordering in the older branches, but Florian argued against it. > > Here's patches doing that. The 9.3 version also applies to 9.2; the 9.1 > version applies back to 8.4.
I have no confidence that this isn't going to be real bad for performance. -- Robert Haas EnterpriseDB: http://www.enterprisedb.com The Enterprise PostgreSQL Company -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers