On 23/03/2010 18:40, Raghavendra G wrote: > > > On Tue, Mar 23, 2010 at 5:05 PM, Ian Rogers > <ian.rogers at contactclean.com <mailto:ian.rogers at contactclean.com>> wrote: > > Yes I know, I reported that bug :-) > > If you're using io-cache then quick-read seems irrelevant as > io-cache has 128K pages internally. > > > io-cache and quick-read perform different functions. Normally while > reading a file, glusterfs (fuse) get following calls from VFS, > > lookup, > open, > read, > . > . > . > read, > flush, > close. > > But quick-read exploits an internal feature of glusterfs present in > lookup to get the entire file in lookup call itself. Hence open, read > and close calls are short-cut at quick-read itself and they don't > reach server thereby saving 3 transactions over network (probably more > due to read). Is it possible for io-cache to detect if a file is smaller than the internal page size (or whatever the cut-off is) and then use the quick-read shortcut itself? In a LAMP situation I'd be wanting to use io-cache but there's also a lot of small files. Having both io-cache and the quick-read cache would just mean the files are double cached - using up twice the memory needed as well as an extra set of memory copies to shuffle things around. Because of this, and the no-total-size-limit bug in quick-read, I'd quite like quick-read to be deprecated and it's functionality added to io-cache rather than fixing the memory limit bug in quick-read. Regards, Ian
