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From: pete%LBL-CSAM@vortex.UUCP
Newsgroups: net.micro.pc
Subject: Re: DOS 2.0 Disk Cache
Message-ID: <3804@sri-arpa.UUCP>
Date: Wed, 3-Aug-83 10:18:16 EDT
Article-I.D.: sri-arpa.3804
Posted: Wed Aug  3 10:18:16 1983
Date-Received: Sun, 7-Aug-83 02:37:32 EDT
Lines: 17

From:  Pete Carah <vortex!pete@LBL-CSAM>

The disk cache in DOS 2.0 is used by the DOS (in this priority order)
for:

        1. Keeping FAT records for drives currently in use.
        2. Keeping directory records for drives currently in use.
        3. Keeping partial sectors being read/written by user code.

When a read/write request involves one or more complete sectors,
generally those sectors will NOT be left in the cache.  Also, if you
have a hard disk you need more buffers than IBM says you should have.
(In my installation, just FAT records are 29 buffers).  If
sub-directories are used, those use lots of buffers too.  I generally
use 40 on start-up, and am considering more.

                                Pete