Re: [CFT][RFC] HT scheduler

Nick Piggin
2003-12-11T08:57:38Z

Nick Piggin wrote:

>
> Don't ask me why it runs out of steam at 150 rooms. hackbench does
> something similar. I think it might be due to some resource running
> short, or a scalability problem somewhere else.

OK, it is spinning on .text.lock.futex. The following results are
top 10 profiles from a 120 rooms run and a 150 rooms run. The 150
room run managed only 24.8% the throughput of the 120 room run.

Might this be a JVM problem?
I'm using Sun Java HotSpot(TM) Server VM (build 1.4.2_01-b06, mixed mode)

ROOMS 120 150
PROFILES
total 100.0% 100.0%
default_idle 81.0% 66.8%
.text.lock.rwsem 4.6% 1.3%
schedule 1.9% 1.4%
.text.lock.futex 1.5% 19.1%
__wake_up 1.1% 1.3%
futex_wait 0.7% 2.8%
futex_wake 0.7% 0.5%
.text.lock.dev 0.6% 0.2%
rwsem_down_read_failed 0.5%
unqueue_me 3.2%