Subject: Re: Disk performance under NetBSD on A3000
To: Michael L. Hitch <osymh@gemini.oscs.montana.edu>
From: Andreas Johansson <ajo@ludd.luth.se>
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
partition).
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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