[OpenAFS] Re: bonnie++ on OpenAFS

[Simon Wilkinson]

On 23 Nov 2010, at 14:15, Andrew Deason <adeason@sinenomine.net> wrote:

> On Tue, 23 Nov 2010 11:23:03 +0000
> Simon Wilkinson <sxw@inf.ed.ac.uk> wrote:
>=20
>> We need a better solution to cache eviction. The problem is that,
>> until very recently, we didn't have the means for one process to
>> successfully flush files written by a different process.
>=20
> I'm not following you; why can the cache truncate daemon not be
> triggered and waited for, like in normal cache shortage conditions?

Because it doesn't do stores. More importantly, because it can't do stores, a=
s it doesn't have access to the credentials that the file was written with. T=
his is the key issue that I was alluding to earlier. The work that Marc has d=
one means that, in master, we do now have access to this information on rece=
nt Linux kernels, where we use it to handle write back. We need to look at g=
eneralising this to other operating systems, and making use of it for cache e=
viction.

S.