Re: O(1) scheduler gives big boost to tbench 192

[Gerrit Huizenga <gh@us.ibm.com>]

In message <E173QiK-0005Bd-00@the-village.bc.nu>, > : Alan Cox writes:
> 
> > Rumor is that on some workloads MQ it outperforms O(1), but it
> > may be that the latest (post K3?) O(1) is catching up?
> 
> I'd be interested to know what workloads ?
 
AIM on large CPU count machines was the most significant I had heard
about.  Haven't measured recently on database load - we made a cut to
O(1) some time back for simplicity.  Supposedly volanomark was doing
better for a while but again we haven't cut back to MQ in quite a while;
trying instead to refine O(1).  Volanomark is something of a scheduling
anomaly though - sender/receiver timing on loopback affects scheduling
decisions and overall throughput in ways that may or may not be consistent
with real workloads.  AIM is probably a better workload for "real life"
random scheduling testing.

gerrit