[ofa-general] Question about perfmgr on OpenSM

[Ira Weiny]

On Fri, 16 Jan 2009 13:46:06 +0100
Nicolas Morey Chaisemartin <nicolas.morey-chaisemartin at ext.bull.net> wrote:

> Hi,
> 
> I'm working on a perf manager plugin for OpenSM.
> It will have quite advanced features which will do more than simply 
> treating received events and extract some informations from OpenSM.
> I have one question though: how are perf manager plugins managed when 
> there are multiple OpenSM running on the same subnet?
> -Is only the one on the MASTER SM started?
> -Are they all started but only the one on the MASTER SM received events 
> (counters/trap)
> -They all start and received events but coming from different par of the 
> subnet
> 

I am not quite sure what you are asking.  Do you have multiple OpenSM's running
on the same subnet perhaps a master and a standby?

The plugins are managed via the OpenSM process.  Each OpenSM which is started
will load the plugins specified in the opensm.conf file.  If those plugins are
the same and would conflict, due to a common database for example, you will
have to synchronize them yourself.  Each SM will report events to all
of it's plugins.

If you are using the new plugin interface I think the easiest implimentation
might be to have your plugin query the SM and if it is in standby ignore the
events being reported.  If the standby becomes master then the plugin could
"turn itself on".

Is this what you are trying to do?

> 
> Due to the data I'm going to use, I need to have only one thread doing 
> its job at a time.
> If there is only one plugin running on the Subnet it'll be fine, if 
> there are several, I'll have to monitor the SM status to ensure only one 
> of my threads is active.

I think this is what you will have to do.  The SM does not communicate the
plugin information to the other SM's on the Subnet.

Hope this helps,
Ira