From mboxrd@z Thu Jan 1 00:00:00 1970 From: Brian Tinsley Subject: Re: what do you do that stresses your filesystem? Date: Fri, 27 Dec 2002 23:27:43 -0600 Message-ID: <3E0D364F.1010008@emageon.com> References: <3E06F360.7000708@namesys.com> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Return-path: list-help: list-unsubscribe: list-post: Errors-To: flx@namesys.com List-Id: Content-Type: text/plain; charset="us-ascii"; format="flowed" To: ReiserFS Cc: Hans Reiser I'm late replying to this one, but I've been on vacation :) Any possible optimizations for the following would be beneficial: * interaction with the Linux NFS server * SMP machines * apps like grep, awk, and sed Any optimizations for the following application characteristics would be beneficial: * Our applications perform multi-threaded streaming I/O (network-to-disk and vice versa) with read/write block sizes varying from 16KB to 64KB; we have files ranging in size from 32KB to 500MB+ (this top end will likely grow into several GB in the near future). * Our directory structure is very broad, but not very deep and files are stored in leaf nodes only. * When a file is created and completely written to disk, it is often re-read in its entirety at least two times within a couple of minutes. * Our database app performs lots of block-based random I/O and fsyncs within a dozen or so large files. Hans Reiser wrote: > We were discussing how to optimize reiser4 best, and came to realize > that us developers did not have a good enough intuition for what users > do that stresses their filesystem enough that they care about its > performance. > > If you just do edits of files it probably does not matter too much > what fs you use. > > Booting the machine seems like one activity that many users end up > waiting on the FS for. Yes? > > Starting up complex and big applications like xemacs and mozilla would > be another. Yes? > > Others? > > Hans > > PS > > reiser4 performance is up a lot recently, and within two weeks I think > cp -r will have been optimized as much as is worth doing. cp -r > accesses files in readdir order, and that does indeed seem worth > optimizing, but soon we will need to optimize more sophisticated > access patterns than that..... > > Hans -- -[========================]- -[ Brian Tinsley ]- -[ Chief Systems Engineer ]- -[ Emageon ]- -[========================]-