Toggling preemption on a running kernel

Toggling preemption on a running kernel

[Matthew Hodgson]

Hi,

I'm trying to compare the performance of some networking code 
(throughput and latency when receiving various volumes of UDP streams) 
between a preemptible and non-preemptible 2.6.24 kernel, and was 
wondering if it is possible to temporarily disable preemption on a 
running preemptible kernel.  Is it just a matter of loading a module 
which calls preempt_enable() at load and preempt_disable() at unload - 
or is that too naive?  Is there an existing way of doing this?

thanks,

Matthew.


-- 
Matthew Hodgson <matthew@mxtelecom.com>
Media & Systems Project Manager
Tel: +44 (0) 845 666 7778
http://www.mxtelecom.com

Re: Toggling preemption on a running kernel

[Bill Davidsen]

Matthew Hodgson wrote:
> Hi,
> 
> I'm trying to compare the performance of some networking code 
> (throughput and latency when receiving various volumes of UDP streams) 
> between a preemptible and non-preemptible 2.6.24 kernel, and was 
> wondering if it is possible to temporarily disable preemption on a 
> running preemptible kernel.  Is it just a matter of loading a module 
> which calls preempt_enable() at load and preempt_disable() at unload - 
> or is that too naive?  Is there an existing way of doing this?
> 
That wouldn't get rid of all the code to support preempt, so it wouldn't 
be useful for comparing much of anything. I think you need to build two 
identical kernels here, with only one difference.

-- 
Bill Davidsen <davidsen@tmr.com>
   "We have more to fear from the bungling of the incompetent than from
the machinations of the wicked."  - from Slashdot