[OpenAFS] Re: Tuning the -daemons.

Andrew Deason adeason@sinenomine.net
Wed, 20 Apr 2011 11:05:03 -0500

On Tue, 19 Apr 2011 10:21:10 -0500
Andrew Deason <adeason@sinenomine.net> wrote:

> The underlying issue I think has always existed: xvcache must be
> write-locked for vcache traversal, and we traverse vcaches looking for
> something to flush, and a flush may hit a fileserver for a
> GiveUpCallBacks call when we flush VCBs when we run out of CBRs. I
> think all of that has always been the case, from looking at git
> history.  ("Always" meaning back to OpenAFS 1.0.)
> Maybe dynamic vcaches made this more likely to be hit, though (which
> would be 1.4.10, Linux-only). Before/without those, I think you have
> to run out of free vcache entries before you hit the relevant code
> path, which I expect happens less often than we ShakeLooseVCaches
> these days.

Actually, the dynamic vcaches ShakeLooseVCaches call didn't lock xvcache
until 1.4.12, when 125589 was fixed (893233f). So, it's probably as
recent as that.

Andrew Deason