*BSD News Article 39003


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From: kstailey@leidecker.gsfc.nasa.gov (Kenneth Stailey)
Newsgroups: comp.os.386bsd.misc,alt.folklore.computers
Subject: Re: BSD sluggish compared to Linux?
Followup-To: comp.os.386bsd.misc,alt.folklore.computers
Date: 06 Dec 1994 17:07:35 GMT
Organization: NASA Goddard Space Flight Center -- Greenbelt, Maryland USA
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In-reply-to: arichfld@cs.sun.ac.za's message of 1 Dec 1994 10:07:04 GMT

If you have SCSI disks under NetBSD you can improve the performance by
[1] setting maxcontig to at least 8 (default is 1) to enable clustering
	(this can be using "tunefs")
[2] setting rotational delays to 0 (must use newfs, sigh)
[3] setting number of rotational positions to 1 (ditto)

If you use newfs you must of course backup & reinstall everything.
The options to get all three are "-a 8 -d 0 -n 1".

This probably applies to other BSD's too.

The problem is that you don't really know with any certainty exactly
where a given disk block is on a SCSI drive since you only talk to the
controller.