[OpenAFS] openafs on Fedora 12?
Simon Wilkinson
sxw@inf.ed.ac.uk
Fri, 11 Dec 2009 17:30:28 +0000
On 11 Dec 2009, at 12:56, Chas Williams (CONTRACTOR) wrote:
> In message <4B220A1A.8080001@pclella.cern.ch>,Rainer Toebbicke writes:
>> With the current "dir" package this means a chunk size of 2MB.
>> Assuming the
>> unit of transfer is still "chunksize" and you do not intentionally
>> fill chunks
>> partially you'd give up a valuable tuning parameter.
>
> hmm... well it is a future problem. i would actually suggest 1MB
> chunks
> for a disk cache anyway. the directory problem is interesting.
> perhaps
> afs should be able to handle partial dir chunks. i would have to look
> into this.
The main issue with handling partial directory chunks would be that
the dir package currently gets passed a single dcache, rather than the
vcache of the directory - so it doesn't currently have any way of
accessing other chunks beyond the one that its passed. Changing that
shouldn't be that difficult in theory - if anything causes pain, I
would imagine it will be the lock hierarchy.
If and when we do extended directories, the directory size is going to
get much larger (you're storing 3 of everything, for a start) so we'll
probably need to address this at some point.
S.