Subject: Re: Disk performance under NetBSD on A3000
To: Michael L. Hitch <>
From: Andreas Johansson <>
List: amiga
Date: 04/25/1995 01:53:57
According to Michael L. Hitch:
> On Apr 24, 12:50pm, Arthur Hoffmann wrote:

>   A question for both Stephen and Arthur - what is the rotational

and me :)

> delay between contiguous blocks for your file system?  I tried dd
> on an older partition (and a slower disk) and got 455902 bytes/sec.
> After using tunefs to set the rotational delay to 0, I got 1048576
> bytes/sec.  [The old default for newfs was 4ms for the rotational
> delay - which is not a good default for current SCSI drives.]

I changed this on a one of my filesystems, and you are right:

delay	4ms	0ms
Write:	580k/s	874k/s
Read:	749k/s	1310k/s

(These are not the same values as my last letters, this is a new, empty

Nevertheless, isn't this a bit slow when raw speed is 3Mb/s?

Is the the A3640 the bad guy?

Is there nothing to be done?

Why is 4ms the default rotational delay for newfs?

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