Joe Conway <mail(at)joeconway(dot)com> writes:
>> Improve spinlock code for recent x86 processors: insert a PAUSE
>> instruction in the s_lock() wait loop, and use test before test-and-set
>> in TAS() macro to avoid unnecessary bus traffic. Patch from Manfred
>> Spraul, reworked a bit by Tom.
> I thought this had been committed to the 7.4 stable branch as well, but
> it appears not.
I am currently chasing what seems to be the same issue: massive context
swapping on a dual Xeon system. I tried back-patching the above-mentioned
patch ... it helps a little but by no means solves the problem ...
regards, tom lane