Re: RSDL v0.30 cpu scheduler for mainline kernels

Siddha, Suresh B
2007-03-15T02:31:11Z

Con,

On Mon, Mar 12, 2007 at 10:58:11AM +1100, Con Kolivas wrote:
> There are updated patches for 2.6.20, 2.6.20.2, 2.6.21-rc3 and 2.6.21-rc3-mm2
> to bring RSDL up to version 0.30 for download here:

I tried this on a Core 2 Quad cpu system(system has 4 cores on a single
package). When I run SPECjbb2000 with number of threads varying from 1-8,
I see ~4.5% perf regression with RSDL (compared to native 2.6.21-rc3) in
the 8 threads case. This I think, is coming from increased number of
context switches, when we have more than one thread(at same user priority) on
the same logical cpu.

Just to see the % increase in number of context switches, I ran 8 infinite
loops (simple while(1); 's) and with 2.6.21-rc3 I see ~70 context switches
every second, whereas with RSDL I see ~530 context switches.

thanks,
suresh