On Tue, Aug 31, 2010 at 12:55 PM, Yeb Havinga <yebhavinga@xxxxxxxxx> wrote: > Scott Marlowe wrote: >> >> On Tue, Aug 31, 2010 at 6:41 AM, Yeb Havinga <yebhavinga@xxxxxxxxx> wrote: >> >>>> >>>> export OMP_NUM_THREADS=4 >>>> >>> >>> Then I get the following. The rather wierd dip at 5 threads is consistent >>> over multiple tries: >>> >>> >> >> I get similar dips on my server. Especially as you make the stream >> test write a large enough chunk of data to outrun its caches. >> >> See attached png. >> > > Interesting graph, especially since the overall feeling is a linear like > increase in memory bandwidth when more cores are active. > > Just curious, what is the 8-core cpu? 8 core = dual 2352 cpus (2x4) 2.1 GHz 12 core = dual 2427 cpus (2x6) 2.2 GHz 48 core = quad 6127 cpus (4x12) 2.1 GHz -- To understand recursion, one must first understand recursion. -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
