[Lustre-discuss] obdfilter-survey customization variables

Sébastien Buisson sebastien.buisson at bull.net
Mon Nov 19 08:53:48 PST 2007


Hello Cliff,

Thanks for the information.
But I am wondering: in the 'disk' case, can we compare the number of 
threads used with a number of clients? or is it more like the number of 
threads running on the OSS and processing read and write requests? or 
maybe it is something completely different?
My question is somehow the same for the 'disk', 'network' and 'netdisk' 
cases. For each case, what does the thread number represent or simulate 
if we want to make an analogy with a fully functional Lustre filesystem?

Regards,
Sebastien.


Cliff White a écrit :
> Sébastien Buisson wrote:
>> Hello everyone,
>>
>> I am looking for some information about some obdfilter-survey 
>> customization variables. The variables I am considering are thrlo and 
>> thrhi.
>>
>> The fact is that I could not find any precise documentation about the 
>> meaning of these variables. Does it depend on the case ('disk', 
>> 'network', 'netdisk') ?
>>
> 
> Thrlo and thrhi determine the number of threads tested. In a perfect 
> world, IO should increase as you add threads. Once you reach the maximum 
> throughput for your hardware, IO should stay steady as you add threads.
> The test will start with thrlo threads, each test pass the number of 
> threads are doubled until reaching thrhi.
> 
> The values you use should not depend on the test case. We usually adjust 
> based on the hardware - a big SMP system will support more threads.
> 
> cliffw
> 
>>
>> Thanks in advance.
>> Sebastien.
>>
>> _______________________________________________
>> Lustre-discuss mailing list
>> Lustre-discuss at clusterfs.com
>> https://mail.clusterfs.com/mailman/listinfo/lustre-discuss
> 
> 




More information about the lustre-discuss mailing list