Xref: utzoo comp.unix.sysv386:3029 comp.unix.questions:27563 Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!uunet!wang!comm.wang.com!lws From: lws@comm.wang.com (Lyle Seaman) Newsgroups: comp.unix.sysv386,comp.unix.questions Subject: Re: Tuning SYSVR3 (Esix Rev D) (LONG!) Message-ID: <1990Dec11.203921.23846@comm.wang.com> Date: 11 Dec 90 20:39:21 GMT References: <1990Nov20.194829.6977@unixland.uucp> <1990Dec02.001311.16727@virtech.uucp> Organization: Wang Labs, Platform Comms. Lines: 28 cpcahil@virtech.uucp (Conor P. Cahill) writes: >In article karl@ficc.ferranti.com (Karl Lehenbauer) writes: >>Anyone have any idea how to reduce these sluggish periods without reducing >>the cache size and without reducing the reliability of the file system >>with respect to power outages or the performance? [ ... re MAXTOUP ... ] >Even if you set this variable to some high value, it is still possible >that at that new time period following a large disk update, the system >will slow down momentarily due to many dirty pages that still need to >be written out, so you may be in a no-win situation. On the other hand, the longer you keep them around, the greater the likelihood that they will be changed again. You've just saved a flush. Rule #1 of performance optimization: "Don't do it." Rule #2 of performance optimization: "Do it later." ( "it" doesn't mean performance optimization...) -- Lyle Wang lws@comm.wang.com 508 967 2322 Lowell, MA, USA uunet!comm.wang.com!lws The scum always rises to the top.