On 12/22/2011 03:10 PM, Dietmar Maurer wrote: >> +Farm has a working directory that is the ground for storing objebts >> +from Sheepdog I/O requests. That being said, the I/O performance for Vm >> +Guests would be practically the same as Simple Store. > > I don't really understand that. You need to compute the sha1 hash and compress > all data - so how can you get the same I/O performance? > Farm only computes the sha1 hash and compress all data in order to 'cache' them, *only* when the snapshot is taken, triggered either by recovery code or user. For other cases, for e.g, serving normal I/O requests, use simple pread/pwrite for object storing like Simple Store, except that farm.write() do a bit bookkeeping. Thanks, Yuan |