Paul Tuckfield <[EMAIL PROTECTED]> writes: >> I used the taskset command: >> taskset 01 -p <pid for backend of test_run.sql 1> >> taskset 01 -p <pid for backend of test_run.sql 1> >> >> I guess that 0 and 1 are the two cores (pipelines? hyper-threads?) on >> the first Xeon processor in the box.
AFAICT, what you've actually done here is to bind both backends to the first logical processor of the first Xeon. If you'd used 01 and 02 as the affinity masks then you'd have bound them to the two cores of that Xeon, but what you actually did simply reduces the system to a uniprocessor. In that situation the context swap rate will be normally one swap per scheduler timeslice, and at worst two swaps per timeslice (if a process is swapped away from while it holds a lock the other one wants). It doesn't prove a lot about our SMP problem though. I don't have access to a Xeon with both taskset and hyperthreading enabled, so I can't check what happens when you do the taskset correctly ... could you retry? regards, tom lane ---------------------------(end of broadcast)--------------------------- TIP 6: Have you searched our list archives? http://archives.postgresql.org