Volanomark regress on ia64

From: Chen, Kenneth W <kenneth.w.chen_at_intel.com>
Date: 2005-09-16 10:40:15
Take a look at http://kernel-perf.sourceforge.net/results.machine_id=26.html

First chart with volanomark benchmark.  It took ~ 11% performance regression
on 2.6.13-git9 and 2.6.14-rc1.

It is not those two particular kernel version have the problem per se.  It
would've shown on 2.6.13-rc1 when default hz rate was switched to 250.  Last
week, I happened to audit the system and made the hz switch and the problem
showed up.

Hz=1000  cpu idle is about 54%, the raw throughput is 74935 msgs/sec
Hz=250   cpu idle is about 58%, the raw throughput is 67246 msgs/sec

I think it has something to do with the scheduler load balance.  While I'm
looking into schedstat and etc.  Posting here for everyone to pour over the
issue.

vmstat/readprofle/schedstat result with 1K hz and 250 hz attached.

- Ken


-
To unsubscribe from this list: send the line "unsubscribe linux-ia64" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Received on Fri Sep 16 10:41:10 2005

This archive was generated by hypermail 2.1.8 : 2005-09-16 10:41:16 EST