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Xref: sserve comp.os.386bsd.misc:4771 comp.os.linux.misc:33246 Newsgroups: comp.os.386bsd.misc,comp.os.linux.misc Path: sserve!newshost.anu.edu.au!harbinger.cc.monash.edu.au!bunyip.cc.uq.oz.au!munnari.oz.au!spool.mu.edu!howland.reston.ans.net!vixen.cso.uiuc.edu!uwm.edu!lll-winken.llnl.gov!noc.near.net!monk.proteon.com!jfw From: jfw@proteon.com (John Woods) Subject: Re: Limits on Linux, FreeBSD and NetBSD Message-ID: <D27L4q.3HM@proteon.com> Sender: news@proteon.com Nntp-Posting-Host: kerplop.proteon.com Organization: Proteon, Inc., Westborough, Ma. References: <pwdD25Htq.58A@netcom.com> <D26603.FzH@park.uvsc.edu> <RICHK.95Jan10103953@netcom17.netcom.com> Date: Tue, 10 Jan 1995 21:31:37 GMT Lines: 17 richk@netcom17.netcom.com (Richard Krehbiel) writes: >In article <D26603.FzH@park.uvsc.edu> Terry Lambert <terry@cs.weber.edu> writes: >> The MAX disk size on SCSI is fixed; if you don't like it, you'll >> have to discover a standard other than SCSI -- actually, I think >> the 8G limit of SCSI isn't surpassed by anything on a PC, but I >You know, I was under the impression that the SCSI protocol has a 32 >bit value for disk sector numbers. With 4G 512-byte sectors, that >comes to 2 terabytes. And SCSI sector size may be other than 512 >bytes, too. The older SCSI read and write commands used 3-byte block numbers, implying a limit of 16 million blocks, or 8GB (512b/s). The 10-byte command block read and write commands use 4-byte block numbers, for 2TB (which should be comfortably excessive for a few years, at any rate). I assume the SCSI-1 definition contained only the 6-byte command forms, but I don't know for sure; the longer command forms were certainly common before SCSI-2 got nailed down.