From owner-freebsd-hackers Sun Apr 21 10:05:49 1996 Return-Path: owner-hackers Received: (from root@localhost) by freefall.freebsd.org (8.7.3/8.7.3) id KAA25865 for hackers-outgoing; Sun, 21 Apr 1996 10:05:49 -0700 (PDT) Received: from fly.HiWAAY.net (root@fly.HiWAAY.net [204.214.4.2]) by freefall.freebsd.org (8.7.3/8.7.3) with SMTP id KAA25860 for ; Sun, 21 Apr 1996 10:05:47 -0700 (PDT) Received: from max7-201.HiWAAY.net by fly.HiWAAY.net; (5.65v3.0/1.1.8.2/21Sep95-1003PM) id AA30863; Sun, 21 Apr 1996 12:05:39 -0500 Message-Id: Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Date: Sun, 21 Apr 1996 12:05:44 -0500 To: "Jonathan M. Bresler" From: dkelly@hiwaay.net (David Kelly) Subject: Re: Archive Anaconda Cc: hackers@freebsd.org Sender: owner-hackers@freebsd.org X-Loop: FreeBSD.org Precedence: bulk At 10:57 AM 4/21/96, Jonathan M. Bresler wrote: > tar uses the native blcksize of the device. Is this the native block size the value reported by "mt stat"? > there is an interblock gap (ala interframe gap on the network-- > no stones, please.) between the records/blocks. the gap is > needed but its just dead tape. a larger block size minimizies > this wastage. Yes, and I understand this gap is larger if the tape can't spool. The rewind/restart process writes a longer gap, rewinds, then when it has data to write starts forward, reads the gap flags and resumes writing over the top of the tail of the gap. It bugs me that my 2940 and Barracuda don't seem to be able to keep the Anaconda completely busy. There are pauses while writing that are not due to the tape reversing to write the next track. The start of a tar write has many of these little starts and stops, then it seems to run about 20 seconds between instances but with no particular pattern. -- David Kelly N4HHE, n4hhe@amsat.org, dkelly@hiwaay.net ============================================================= To invent, you need a good imagination and a pile of junk. - Thomas Edison