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Path: sserve!manuel!munnari.oz.au!uunet!spool.mu.edu!sdd.hp.com!swrinde!news.dell.com!uudell!obiwan!bob From: bob@obiwan.uucp (Bob Willcox) Newsgroups: comp.unix.bsd Subject: Re: Tape on 386bsd... Message-ID: <Bv474n.HKF@obiwan.uucp> Date: 25 Sep 92 03:31:35 GMT References: <q83o7rs@sgi.sgi.com> Organization: Bob's Place, Austin TX Lines: 29 In article <q83o7rs@sgi.sgi.com> rpw3@rigden.wpd.sgi.com (Rob Warnock) writes: >randy@chinet.chi.il.us (Randy Suess) writes: >+--------------- >| bob@obiwan.uucp (Bob Willcox) writes: >| >it appears to be missing the first 2KB of each block read. (I was using >| >a buffer size of 2MB as I recall). >| >| I am pretty sure this is a FAQ. Do NOT use any buffering. >| just tar cf /dev/wt0 and cpio -oc > /dev/wt0. There is a >| reason for this, but I can't find my notes. It is slow, but works. >+--------------- > >Well, you don't have to use *no* buffering, just keep it under 64 KB (I think). >I have no problems with "cpio -B", which uses 5120-byte blocks, and it goes >a *lot* faster than "cpio" without the "-B". ("Tar" defaults to 10240, which >also works well.) Thanks for the tip. Turns out I was able to get up to 485KB (successfully) before encountering problems. I generally use afio for backing up and was able to determine (imperically) that with a buffer size of 5120 and a count of 97 (for at total of 485KB per block) my reads of the tape worked okay. Beyond that I encountered problems again. Note that writing 2MBs at a time seems to work just fine. Bob -- Bob Willcox ...!{rutgers|ames}!cs.utexas.edu!uudell!obiwan!bob Phone: 512 258-4224 (home) 512 838-3914 (work)