Fergus Henderson wrote:
On Thu, Apr 30, 2009 at 9:07 PM, Robert W. Anderson
<anderson...@poptop.llnl.gov <mailto:anderson...@poptop.llnl.gov>> wrote:
Fergus Henderson wrote:
The include server could be the bottleneck. What's the CPU
usage for the include server process?
Or it could be disk I/O. Try iostat or vmstat to profile that.
After some more experimentation, I think I may have a clue what's
going on here. I think I may be getting bound up in context
switching costs, both in my single node performance and on localhost
using distcc.
On a single node:
-j4: 24 million context switches @ 10us = 4m
-j8: 96 million context switches @ 10us = 16m
...
I don't understand why doubling the job count increases context
switching by 4x. Any insights appreciated.
You mentioned earlier that your host has four processors.
No, I mentioned a few times that it has 16 processors.
Thanks,
--
Robert W. Anderson
Center for Applied Scientific Computing
Email: anderson...@llnl.gov
Tel: 925-424-2858 Fax: 925-423-8704
__
distcc mailing list http://distcc.samba.org/
To unsubscribe or change options:
https://lists.samba.org/mailman/listinfo/distcc
