Path: utzoo!attcan!utgpu!news-server.csri.toronto.edu!clyde.concordia.ca!uunet!virtech!cpcahil
From: cpcahil@virtech.uucp (Conor P. Cahill)
Newsgroups: comp.unix.i386
Subject: Re: Tape backup performance on 386 ISA/EISA systems
Keywords: tape, performance, 386
Message-ID: <1990Jun10.114934.17744@virtech.uucp>
Date: 10 Jun 90 11:49:34 GMT
References: <1060@sixhub.UUCP> <770@mwtech.UUCP> <1123@sixhub.UUCP>
Reply-To: cpcahil@virtech.UUCP (Conor P. Cahill)
Organization: Virtual Technologies Inc., Sterling VA
Lines: 16

In article <1123@sixhub.UUCP> davidsen@sixhub.UUCP (bill davidsen) writes:
>  As I noted before, that was a typo, the low (fragmented) rate was
>300KB/min (not /sec), when the disk is not fragmented and the tape
>streams the rate is 4MB/min (there I typed it right twice).

The only reason I could see for this kind of difference is that you are
using backup software that does not have a large tape buffer (i.e. tar).

Using a tape backup archiver with large buffers (like cpio -C 102400)
will negate most of the effect of a fragmented disk on tape streaming.


-- 
Conor P. Cahill            (703)430-9247        Virtual Technologies, Inc.,
uunet!virtech!cpcahil                           46030 Manekin Plaza, Suite 160
                                                Sterling, VA 22170