Re: RSDL 0.31 causes slowdown

[Tim Chen <tim.c.chen@linux.intel.com>]

On Fri, 2007-03-23 at 13:40 +1100, Con Kolivas wrote:

> 
> Volanomark is a purely yield() semantic dependant workload (as
> discussed many times previously). In the earlier form of RSDL I
> softened the effect of sched_yield but other changes since then have
> made that softness bordering on a noop. Obviously when sched_yield is
> relied upon that will not be enough. Extending the rr interval simply
> makes the yield slightly more effective and is not the proper
> workaround. Since expiration of arrays is a regular frequent
> occurrence in RSDL then changing yield semantics back to expiration
> should cause a massive improvement in these values, without making the
> yields as long as in mainline. It's impossible to know exactly what
> the final result will be since java uses this timing sensitive yield
> for locking but we can improve it drastically from this. I'll make a
> patch soon to change yield again.
> 

Con, 

The new RSDL 0.33 has fully recovered the loss in performance for
Volanomark.  The throughput for Volanomark is at the same level as
mainline 2.6.21-rc4 kernel.

Tim