Yeb Havinga wrote:
The rather wierd dip at 5 threads is consistent over multiple tries
I've seen that twice on 4 core systems now. The spot where there's just one more thread than cores seems to be the worst case for cache thrashing on a lot of these servers.
How much total RAM is in this server? Are all the slots filled? Just filling in a spreadsheet I have here with sample configs of various hardware.
Yeb's results look right to me now. That's what an AMD Phenom II X4 940 @ 3.00GHz should look like. It's a little faster, memory-wise, than my older Intel Q6600 @ 2.4GHz. So they've finally caught up with that generation of Intel's stuff. But my current desktop quad-core i860 with hyperthreading is nearly twice as fast in terms of memory access at every thread size. That's why I own one of them instead of a Phenom II X4.
-- Greg Smith 2ndQuadrant US Baltimore, MD PostgreSQL Training, Services and Support g...@2ndquadrant.com www.2ndQuadrant.us -- Sent via pgsql-performance mailing list (pgsql-performance@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
