[OpenAFS] Re: Performance issue with "many" volumes in a single /vicep?

Tom Keiser tkeiser@sinenomine.net
Thu, 25 Mar 2010 01:39:20 -0400

On Thu, Mar 25, 2010 at 12:39 AM, Andrew Deason <adeason@sinenomine.net> wr=
> On Wed, 24 Mar 2010 23:43:32 -0400
> Tom Keiser <tkeiser@sinenomine.net> wrote:
>> What I was trying to say is if the observed performance regression
>> involves either the volserver, or the salvager, then it could involve
>> partition lock contention. =A0However, this will only come into play if
>> you're running a lot of vos jobs in parallel against the same vice
>> partition...
> The volserver won't cause partition lock contention with itself. If
> another thread already holds the partition lock, other threads won't
> wait for it, iirc. (At least, in 1.4)

Heh.  I should have quite while I was ahead.  Yes, what Andrew said.
These lock contention problems really only manifested themselves on
older DAFS builds where we saw lots of demand salvage procs contending
against volserver transactions for the partition lock.