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Newsgroups: comp.unix.bsd.freebsd.misc,comp.os.linux.hardware Path: euryale.cc.adfa.oz.au!newshost.anu.edu.au!harbinger.cc.monash.edu.au!simtel!pravda.aa.msen.com!news1.best.com!sgigate.sgi.com!enews.sgi.com!lll-winken.llnl.gov!osi-east2.es.net!cronkite.nersc.gov!qiclab.scn.rain.com!psgrain!fizban.solace.mh.se!demos!satisfy.kiae.su!carrier.kiev.ua!info.elvisti.kiev.ua!office.elvisti.kiev.ua!stesin From: stesin@elvisti.kiev.ua (Andrew V. Stesin) Subject: Re: Tape backup speed FreeBSD v. Linux Followup-To: comp.unix.bsd.freebsd.misc,comp.os.linux.hardware X-Newsreader: TIN [version 1.2 PL2+] Sender: usenet@info.elvisti.kiev.ua (ElVisti USENET) Organization: Electronni Visti InformAgency (ElVisti) Message-ID: <DHAxtK.H9p@info.elvisti.kiev.ua> References: <1995Oct30.090118.28117@state.systems.sa.gov.au> X-Nntp-Posting-Host: office.elvisti.kiev.ua Date: Tue, 31 Oct 1995 07:22:32 GMT Lines: 28 Xref: euryale.cc.adfa.oz.au comp.unix.bsd.freebsd.misc:8430 comp.os.linux.hardware:20660 Hello chdemgt@state.systems.sa.gov.au; quoting you from comp.unix.bsd.freebsd.misc <1995Oct30.090118.28117@state.systems.sa.gov.au> : : The something was wrong could be detected at once by ear. On FreeBSD the tape : seems to run forward for 1.5 sec and then back for 1.5 sec. This continues : without intermission during the backup. On Linux the tape seems to run : forwards for long periods of time, very occasionally reversing once. There is a known problem in wt.c driver since old 1.1 days. With an Archive FT-60 (ancient 60Mb streamer) this sympthoms were even worse; but I've seen people running Archive 150Mb (or 120?) streamers pretty nice. Don't know exactly what happens. My former chief suggested adding double-buffering scheme to the driver, but I seriously doubt that Archive streamer controllers are so damn fast to overrun ISA performance. Seems that there is some unknown 'X' in controller programming info that played the joke. : Michael Talbot-Wilson -- With best regards -- Andrew Stesin. +380 (44) 2760188 +380 (44) 2713457 +380 (44) 2713560 "...Good marketing beats good technology, every time". True?