Hi Aaron,

Thanks for the reply. I agree ultimately the amount of CPU usage is what
that matters. But still seems high occupying kernel data structures.
Infact we are planning to run multiple MDTs for different
logical-volumes on same node. The worry is the number of processes might
dramatically increase, like 400 processes for two Lustre MDT set. 

We are designing for a low-end system with system memory as low as
256MB, these resources are precious :-)

- Sridharan 

> -----Original Message-----
> From: Aaron Knister [mailto:[EMAIL PROTECTED] 
> Sent: Wednesday, February 07, 2007 8:35 AM
> To: Sridharan Ramaswamy (srramasw)
> Cc: Andreas Dilger; [email protected]
> Subject: Re: [Lustre-discuss] Number of processes in Lustre tunable?
> 
> There is no real reason that I see to reduce the number of Lustre 
> processes. It won't cause any ill effects on other processes running. 
> Lustre is heavily multi threaded hence the large number of 
> lustre procs.
> 
> Sridharan Ramaswamy (srramasw) wrote:
> > Hi Andreas,
> >  
> > I didn't see any reply earlier. Can you please comment on this 
> > question on number of Lustre processes?
> >  
> > - Sridharan
> >
> >     
> --------------------------------------------------------------
> ----------
> >     *From:* [EMAIL PROTECTED]
> >     [mailto:[EMAIL PROTECTED] *On Behalf Of
> >     *Sridharan Ramaswamy (srramasw)
> >     *Sent:* Tuesday, January 23, 2007 10:39 AM
> >     *To:* [email protected]
> >     *Subject:* [Lustre-discuss] Number of processes in 
> Lustre tunable?
> >
> >      
> >     I'm tring to measure the overhead of having Lustre on the
> >     system.  Among other things, I noticed it starts lot of 
> processes,
> >      
> >     root      4565     1  0 Jan03 ?        00:00:00 [ll_mdt_attr_14]
> >     root      4636     1  0 Jan03 ?        00:00:01 [ll_ost_13]
> >     root      4651     1  0 Jan03 ?        00:00:08 [ll_ost_io_13]
> >     root      4550     1  0 Jan03 ?        00:00:03 [ll_mdt_14]
> >     root      4516     1  0 Jan03 ?        00:00:00 [ldlm_cb_31]
> >     I can account about 200 processes related to Lustre on an OST
> >     node. That seems a lot considering we would like to run other
> >     applications on the same node. Is it possible to tune 
> these number
> >     of processes down? Say reduce 32 ldlm process to about 8. What
> >     kind of performance degradation to expect if we can do that?
> >      
> >     thanks,
> >     Sridharan
> >
> > 
> --------------------------------------------------------------
> ----------
> >
> > _______________________________________________
> > Lustre-discuss mailing list
> > [email protected]
> > https://mail.clusterfs.com/mailman/listinfo/lustre-discuss
> >   
> 

_______________________________________________
Lustre-discuss mailing list
[email protected]
https://mail.clusterfs.com/mailman/listinfo/lustre-discuss

Reply via email to