Here are the _general_ guidelines for using performance translators: * write-behind: Almost always helps on the client side, because it decreases write latency for applications. Using it is a good idea. * io-threads: Almost always helps on the server side. We recommend using it just below the protocol/server translator. * read-ahead: Helps on the client side if your applications read files in sequential order a lot. * io-cache: Using io-cache on the client side would make sense if you have a bunch of data that is frequently used (for example, a bunch of small image files that are needed for every page on a website). Also, as you said, if you have a lot of RAM, you might find io-cache useful. As for io-threads above/below unify, there is not much to be gained by using io-threads on the client side, since there are no slow operations on the client side (just a straight code path from the application to the server). Using it on the server makes sense because it lets GlusterFS do other useful work while one thread is waiting for a read/write from/to the underlying filesystem finishes. You might also want to look at the booster shared library which can provide a major performance enhancement. Vikas -- Engineer - Z Research http://gluster.com/
