[OpenAFS] Performance

[emoy@apple.com]

Could the slowness you see with your dd write test be related to the  
cache exhaustion issue that I raised recently, when writing a file  
larger than your cache size.  Your test writes a 1 GB file, so if your  
cache is smaller than this, you will see poor performance once your  
cache size is exceeded.
------------------------------------------------------------------------ 
--
Edward Moy
Apple Computer, Inc.
emoy@apple.com

(This message is from me as a reader of this list, and not a statement
from Apple.)

On Thursday, February 27, 2003, at 11:15  AM, Nathan Ward wrote:

> I see pretty bad performance to tell you the truth.
> I can read and write ~60mb/s directly to my raid array, but when using  
> OpenAFS (locally or remotely) to the same array, I get around  
> 6-10MB/s, I have seen up to 25MB/s over a peice of 1000Mbps fibre.  
> Client and Server are both dual P3-1ghz with 1024mb ram. I notice the  
> context switches on the server at this time jump to ~10000/s, and on  
> the client ~40000/s. I imagine this is the source of my slowdown, but  
> I havn't had a chance to look into it.
>
> I'd be interested if anyone else has the same level of context  
> switches going on.
>
> This is while doing a large sequential write operation (dd  
> if=/dev/zero of=/afs/alb-nz.esphion.com/public/dd.out bs=256k  
> count=4096).
>
> Michael Robokoff wrote:
>
>> Does anyone have any Open AFS performance information they can share  
>> with me. I plan on doing a couple benchmarks and I would like to have  
>> some idea of what to expect.