[OpenAFS] Debugging AFS sluggishness on MacOS 10.5.7?

Derrick Brashear shadow@gmail.com
Mon, 29 Jun 2009 11:17:49 -0400


>> Is NFS using TCP in your environment? If it is, you haven't ruled out
>> network yet.
>
> NFS is using TCP, but, as my local sysadmin suggested, I mounted the same
> NFS share using the UDP protocol, and the performance is equivalent to the
> TCP mount. So it's not UDP per se.

I doubt, in that case, that it's UDP.

>> - It's not an OpenAFS version problem. I upgraded from 1.4.6 to 1.4.10
>> with no resulting improvement in the performance. (I didn't do a clean
>> install - and I'm going to try that - but I don't have much confidence that
>> that will have any effect.)
>>
>> I doubt it will, though what's in /var/db/openafs/etc/config/afsd.options?
>
> I did the clean install, and the problem persists.
>
> I don't have an afsd.options file, but I do have afs.conf. Here's the
> OPTIONS value:
>
> OPTIONS="-afsdb -stat 2000 -dcache 800 -daemons 3 -volumes 70 -dynroot
> -fakestat -all"
>
> It's most likely the default.
>
>> - It's not a new server problem. My research computing admin tells me that
>> nothing has changed in the AFS configuration in the last month except that
>> they moved some volumes from one machine to another, but I can't believe
>> that would make any difference, since they're both on the same subnet and
>> neither of them is a machine directly listed in CellServDB.
>> - It MIGHT be a Mac OS problem. I upgraded to 10.5.7 about a month ago,
>> and it's possible that the new behavior coincided with the install, although
>> it's unlikely.
>>
>> from what?
>
> Upgraded from 10.5.6.
>
> 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.


The questions I'd first ask are
-is anti-virus in play?
-is VPN in play?

And the first suggestion for gathering further information:
edit the OPTIONS in afs.conf to enable memcache (-memcache) and see if
the performance changes.

-- 
Derrick