From owner-freebsd-hackers  Wed Apr 26  7:57: 7 2000
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Date: Wed, 26 Apr 2000 16:55:58 +0200 (EET)
From: Narvi <narvi@haldjas.folklore.ee>
To: Matthew Dillon <dillon@apollo.backplane.com>
Cc: Michael Bacarella <mbac@nyct.net>,
	Alfred Perlstein <bright@wintelcom.net>,
	Kevin Day <toasty@dragondata.com>, hackers@FreeBSD.ORG
Subject: Re: Double buffered cp(1)
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On Sat, 22 Apr 2000, Matthew Dillon wrote:

[snip]

>     disk itself is probably the bottleneck.  Disk writes tend to be
>     somewhat slower then disk reads and the seeking alone (between source
>     file and destination file), even when using a large block size, 
>     will reduce performance drastically verses simply reading or writing
>     a single file linearly.  Double buffering may help a disk-to-disk
>     file copy, but I doubt it will help a disk-to-same-disk file copy.
> 

Wouldn't coping the file to another disk and then back to the original one
than just a simple copy in some cases be faster then?

After all, you are saving a lot of head seeks.

> 					-Matt
> 					Matthew Dillon 
> 					<dillon@backplane.com>
> 



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