On Tue, Oct 13, 2015 at 2:32 AM, Heikki Linnakangas <hlinnaka@xxxxxx> wrote: > 80% of the CPU time is spent in the b-tree comparison function. In the logs, my duration per COPY command increases from about 1400ms for one process to about 3800ms when I have four running concurrently. That's really my only data point, unfortunately. Strace isn't super helpful because it just says 70-ish% of the time is wait4, but that's not significantly different than the results using one process. Everything else is bog standard default. I bumped up checkpoint_segments to avoid checkpoints during the test, and increased work_mem and maintenance_work_mem to avoid disk affecting results, and still got the same behavior. I wasn't blaming the patch. :) I thought it didn't get merged or something, and after learning that wasn't the case, my only theory went out the window. I'm a bit stuck, because this seems incredibly wrong. I'll keep digging. -- Shaun Thomas bonesmoses@xxxxxxxxx http://bonesmoses.org/ -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
