Re: [PATCH] opensm: enable perfmgr build by default

Alex Netes
2011-07-10T08:54:18Z

Hi Ira,

On 10:13 Fri 08 Jul , Ira Weiny wrote:
> On Fri, 8 Jul 2011 09:23:50 -0700
> Hal Rosenstock <hal-LDSdmyG8hGV8YrgS2mwiifqBs+8SCbDb@public.gmane.org> wrote:
>
> > Ira,
> >
> > On 7/8/2011 12:06 PM, Ira Weiny wrote:
> > > However, when we first put the PerfMgr in OpenSM there was some concern for developers who may be using OpenSM in an embedded environment.
> >
> > Do you recall the specific concerns ? I forget and would rather not dig
> > them out unless really necessary...
>
> If I recall there was no "specific" concern just that someone _may_ do this.
>
> Also I think there was some concern about the PerfMgr taking too much processing time with it's threads. But I think that is configurable by the number of SMP's on the wire and turning it off if one prefers a different model.
>

PerfMgr adds ~200K to opensm binary (34K when stripped).
During runtime PerfMgr adds ~270K to opensm memory allocation, when running
with PerfMgr disabled.

During the opensm initialization, osm_perfmgr_init() and osm_perfmgr_bind()
are called even if PerfMgr is disabled. I guess it's needed, if we want to
enable PerfMgr later on the fly.
I'm not sure though, how calling to osm_perfmgr_bind() affects performance.

One more thing, perfmgr_sweep() is called each (pm->sweep_time_s * 1000) no
matter if PerfMgr is enabled or disabled. Though it does nothing, I think it's
better to execute perfmgr_sweep() only when PerfMgr is enabled.

-- Alex