[OpenAFS] Debugging AFS sluggishness on MacOS 10.5.7?

Felix Frank Felix.Frank@Desy.de
Wed, 01 Jul 2009 07:49:14 +0200

Samuel Bayer wrote (Tue Jun 30 2009 16:24:32 GMT+0200 (CEST))
> Felix Frank wrote:
>>> Another tidbit that is either hopelessly banal because I don't 
>>> understand how AFS works, or really important: WRITING to the same 
>>> AFS directory works fine. I copy the file from the directory to my 
>>> local disk and it takes 4 minutes; I delete the file from the remote 
>>> disk and write it there from my local disk and it takes 30 seconds.
>> Just a side remark: If the file is smaller than your cache, then this 
>> is probably the cache manager writing to the cache, which is supposed 
>> to be fast. I'd expect a rather sharp corner in the write performance 
>> curve as soon as your amount of data surpasses disk cache size.
> Thanks, but this appears not to be the problem. My cache is 30MB, and 
> the file I'm exchanging is 70MB. I'm watching the copy progress in the 
> Finder, and it doesn't appear to slow down appreciably when it hits the 
> halfway mark.

Note that this only applies to disk cache (plus, I'm somewhat suspicious 
of third party progress bars, as the logic behind those cannot easily be 

Anyway, a cache bottleneck would result in a longer overall write time, 
which is obviously not the case. For a disk cache, 30MB is rather slim. 
A larger disk cache may be of benefit.

...but do stick with memcache if it works well for you.

  - Felix