SolrCoud cluster heavily depends on data locality and high I/O, thus any NFS with access to disk array over the network is multitude times slower than direct I/O and must be avoided. Classical JBOD (just a bunch of disks) config + memory mapped files ensure high performance.
On Wed, Nov 5, 2014 at 4:27 PM, Walter Underwood <wun...@wunderwood.org> wrote: > My experience was with Solr 1.2 and regular old NFS, so that was probably > worst case. I was very surprised that it was that bad, though. > > So benchmark it before you assume it is fast enough. > > wunder > Walter Underwood > wun...@wunderwood.org > http://observer.wunderwood.org/ > > On Nov 5, 2014, at 12:27 AM, Toke Eskildsen <t...@statsbiblioteket.dk> > wrote: > > > On Tue, 2014-11-04 at 22:57 +0100, Gili Nachum wrote: > >> My data center is out of SAN or local disk storage - is it a big no-no > to > >> store Solr core data folder over NAS? > > > > It depends on your NAS speed. Both Walter and David are right: It can > > perform really bad or quite satisfactory. We briefly experimented with > > using 400GB of Isilon ( http://www.emc.com/isilon ) SSD cache as backend > > for a searcher. As far as I remember, speed was surprisingly fine; about > > 3 times slower than with similar local storage. As we needed 20TB+ of > > index, it would be too expensive for us to use the enterprise NAS system > > though (long story). > > > >> The NAS mount would be accessed by a single machine. I do care about > >> performance. > > > > I have a vision of a off-the-shelf 4-drive box Gorilla-taped to the side > > of a server rack :-) > > > > Or in other words: If the SAN is only to be used by a single machine, > > this will be more of a kludge than a solid solution. Is it not possible > > to upgrade local storage to hold the data? How large an index are we > > talking about? > > > >> If I do go with NAS. Should I expect index corruption and other > oddities? > > > > Not that I know of. As the NAS is dedicated, you won't compete for > > performance there. Do check if your network is fast enough though. > > > > > > - Toke Eskildsen, State and University Library, Denmark > > I highly recommend Gorilla Tape for semi-permanent kludges. > > > >
