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Path: euryale.cc.adfa.oz.au!newshost.anu.edu.au!harbinger.cc.monash.edu.au!news.mira.net.au!Germany.EU.net!main.Germany.EU.net!Frankfurt.Germany.EU.net!howland.reston.ans.net!nntp.coast.net!news.kei.com!newsfeed.internetmci.com!malgudi.oar.net!hyperion.wright.edu!echoes.wittenberg.edu!bob.wittenberg.edu!mandrews From: mandrews@bob.Wittenberg.EDU (Mike Andrews) Newsgroups: news.software.nntp,comp.unix.bsd.freebsd.misc Subject: Re: FreeBSD 2.1.5, INN 1.4unoff4, and mmap() Date: 18 Jul 96 12:38:40 GMT Organization: Wittenberg University, Springfield OH Lines: 46 Distribution: inet Message-ID: <mandrews.837693520@bob.wittenberg.edu> References: <mandrews.837437077@bob.wittenberg.edu> <4sdk50$9cp@news.demos.su> <4sdndm$27k@brasil.moneng.mei.com> <4se8tq$sgf@news.demos.su> <4sg80v$3uu@brasil.moneng.mei.com> <4sggo5$ls@news.demos.su> NNTP-Posting-Host: bob.wittenberg.edu X-Newsreader: NN version 6.5.0 #8 (NOV) Xref: euryale.cc.adfa.oz.au news.software.nntp:24503 comp.unix.bsd.freebsd.misc:23905 andy@sun-fox.demos.su (Andrew A. Vasilyev) writes: >Joe Greco (jgreco@brasil.moneng.mei.com) wrote: >> My point was why would you care about overall disk bandwidth, so why would >> you run a bandwidth test? > Only to say that there is big gap: metadevice speed vs FS speed. > I hope the optimisation will be done: ccd is very young now :) >> "~S"? >> If you mean the size of the article, you are wrong. > Could you provide the theoretical value of stripe size for multiple > reading/writing of small files? >> No, you're forgetting - to retrieve an article requires multiple accesses. >> You need to do multiple directory lookups, etc. If you really think about > Well - here is the weakness of FreeBSD FS: when you access the file > in a large directory in Solaris the lookup goes from the cache, you > say in Free too, but the tests show that the efficiency of its cache > is worse than of Solaris. So multiple lookups should not worry you > on well-written FS :) > So if we return to the thread start: in FreeBSD we have buggy mmap() > and soggy ccd together with not so good directory cache. All these > cause me to say the better platform for heavy loaded news server is > Solaris. :(( Well, the thread wasn't about FreeBSD vs. Solaris... The thread was mostly about "can I use mmap()", and it seems I still can't. I can deal with waiting for 2.2. As far as optimal stripe size... this is not a "heavily loaded" news server. We are an end node with only one tiny partial outgoing feed, so it makes more sense to optimize for multiple article writes instead of reads. I set it up for a stripe size of 116 instead of 65536 (mostly because I read Joe's message too late :) and it seems to be pretty speedy, even though it's optimized for overall throughput and not optimized for news's special needs. We'll see... -- -- Mike Andrews - mandrews@wittenberg.edu, mandrews@termfrost.org (NeXT) -- Programmer/Analyst, systems/mail/web/netnews guy, Wittenberg University -- http://www.termfrost.org/~mandrews/ "why..."