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Path: sserve!newshost.anu.edu.au!harbinger.cc.monash.edu.au!bunyip.cc.uq.oz.au!munnari.oz.au!constellation!osuunx.ucc.okstate.edu!newsfeed.ksu.ksu.edu!moe.ksu.ksu.edu!vixen.cso.uiuc.edu!howland.reston.ans.net!noc.near.net!news.delphi.com!usenet From: John Dyson <dysonj@delphi.com> Newsgroups: comp.os.386bsd.questions Subject: Re: Why is it so slow? Date: Fri, 27 May 94 22:47:01 -0500 Organization: Delphi (info@delphi.com email, 800-695-4005 voice) Lines: 38 Message-ID: <Jc8Oey1.dysonj@delphi.com> References: <CqGzrI.9vq@oea.hacktic.nl> <CqHFDB.4GJ@rex.uokhsc.edu> NNTP-Posting-Host: bos1a.delphi.com X-To: Benjamin Z. Goldsteen <ben@rex.uokhsc.edu> The *BSD kernels do end up being fairly large. Part of the problem is the fixed sized buffer cache. The system should not be *that* slow, I have used it during our testing on 4MB machines -- and if you do normal user things, runs ok. The GCC compiler can be quite large during compiles and can thrash the system. Also, our fp emulation is *definitely* not up to par (this is not a problem if you have a math chip) on 1.1R. That has been resolved to a certain extent in -current (and soon to be 1.1.5??) There are going to be mods made to portions of the system in FreeBSD to share memory more evenly between processes and buffer cache in a very elegant fashion, but that is at least 3mos away for 4.4. I strongly suggest that X in 4MB is not fun (I have run it in 2MB and it is awful.) Except for the above caveats -- the system runs about as fast as it can in 4MB. We have tuned the page management to be about as good as it can be (and for a kernel build is quite reasonable.) The 1.1R doesn't have the full suite of VM changes (and in fact has the most innocuous ones.) The -current stuff does have even more significant improvements. If you can quantify and specify the performance problems that you are having more precisely -- maybe we can help. There are some delays in the terminal support code -- and the tset suggestion made in an earlier posting has helped some people. It is expensive for me to communicate with people when I am using Delphi, so if you have any more information or questions, let me know at my email address "dyson@implode.root.com". If we can nail down the problem that you are having, then we can post the solution. But, the fact is, FreeBSD does get about as much performance as almost anybody else can get -- considering the size of the kernel, etc. One more minor thing, that it appears that our libraries are optimized very well for i386/i486, but we will have to do a little work to spiffy them up for Pentium. Its not bad, but just saying that we'll be doing better later... John dyson@implode.root.com