Path: utzoo!news-server.csri.toronto.edu!rpi!zaphod.mps.ohio-state.edu!swrinde!elroy.jpl.nasa.gov!ames!haven!decuac!hussar.dco.dec.com!mjr From: mjr@hussar.dco.dec.com (Marcus J. Ranum) Newsgroups: comp.unix.ultrix Subject: Re: Will prestoserve help a client Message-ID: <1991Mar18.144323.11011@decuac.dec.com> Date: 18 Mar 91 14:43:23 GMT References: <1991Mar11.204258.29415@cunixf.cc.columbia.edu> <1991Mar11.213800.7596@decuac.dec.com> Organization: Digital Equipment Corp., Washington Ultrix Resource Center Lines: 23 pcg@test.aber.ac.uk (Piercarlo Antonio Grandi) writes: >Rethorical question: how many megabytes of extra disk buffer cache on >the client or server can you buy for the cost of one NFS accelerator? Straight-man answer: Since the bottleneck is usually writes, especially with NFS, added cache in the client won't help much if you do any writes (unless you're paging a lot, in which case paging == writes, and adding memory will reduce writes). Since writes on the server are also synchronous, adding extra disk buffer cache will only improve your read times, not your write times. Rhetorical answer: How much local disk can you buy for the cost of all that memory? If performance is your problem, and you're doing writes, NFS should probably not be part of your solution. mjr. -- The world is just backing store for virtual reality games.