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Date:	Wed, 31 Jul 2002 23:17:03 PST7
From:	Peter Skye <pskye@peterskye.com >
Reply-To:	scoug-help@scoug.com
To:	scoug-help@scoug.com
Subject:	SCOUG-Help: Re: Drive Image Backups

Content Type: text/plain

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Steven Levine wrote:
>
> To me, it appears that BA2K does I/O much more effeciently
> than XCOPY, so even without compression, BA2K will be faster.

I'm sure you're correct. It takes time to create a file; if I'm backing
up 20,000 files then XCOPY has to create every one of them on the backup
volume (seek & read the directory, create the new file, split/rebalance
the tree if necessary, then seek to the start of the file) but BA2K (or
any other program making one-out-of-many) only has to create one file.

The quick raw I/O test for anyone with BA2K installed would be to create
a 1 GB test file, then see how long it takes to XCOPY it to the backup
drive and also see how long it takes to back it up with BA2K. Hint for
making a 1 GB file: create a file & seek to 1,000,000,000 (in Rexx set
NUMERIC 10); if you don't like your GBs in round zeroes use
1024*1024*1024. :)

- Peter

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