[Lustre-discuss] Modifying Lustre network (good practices)

[Olivier Hargoaa]

Johann Lombardi a écrit :
> Hi Olivier,
> 
> On Thu, May 20, 2010 at 07:12:45PM +0200, Olivier Hargoaa wrote:
>> But you couldn't know but we already ran lnet self test unsuccessfully. 
>> I wrote results as answer to Brian.
> 
> ok. To get back to your original question:
> 
>> Currently Lustre network is bond0. We want to set it as eth0, then eth1,
>> then eth2 and finally back to bond0 in order to compare performances.
>> Therefore, we'll perform the following steps: we will umount the
>> filesystem, reformat the mgs, change lnet options in modprobe file,
>> start new mgs server, and finally modify our ost and mdt with
>> tunefs.lustre with failover and mgs new nids using "--erase-params" and
>> "--writeconf" options.
> 
> Since you can reproduce the perf drop with LST, you don't need to change
> the filesystem configuration to test the different lnet configs. I would
> just umount the filesystem, reconfigure lnet by changing the modprobe file
> and run LST.

Hi Johann,

Yes you are right. We plan to run more LNET tests on wednesday.
First we will test bonding again with LNET (read and write), then 
deactivate bonding and test eth2, then eth3 and finally run lst with 
both eth2 and eth3 without bonding.
Depending on the results we will decide to try a lustre level test 
(iozone) and therefore we will modify Lustre filesystem lnet parameters.

Thanks everybody.

> 
> Johann
> 
> 


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Olivier, Hargoaa
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