Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!uunet!efi!tim
From: tim@efi.com (Tim Maroney)
Newsgroups: comp.sys.mac.programmer
Subject: The File System Cache Slows Down File Operations
Message-ID: <1990Dec18.011129.6432@efi.com>
Date: 18 Dec 90 01:11:29 GMT
Organization: Electronics For Imaging, Inc.
Lines: 13

The message hasn't arrived here yet, but I received a forwarded message
expressing skepticism that the new DayStar SCSI cache card could
actually speed up compiles.  The evidence submitted was essentially,
"After all, try turning up the file system cache on your Mac and watch
the compiles go slower!"  This is a true and remarkable fact, but it's
solely because the FS cache uses a sequential search algorithm that
degrades severely for any cache greater than 64K or 128K.  There has
been a lot of discussion of the issue on MACAPP.TECH$ lately.  A smart
caching algorithm, especially given dedicated hardware, has the
potential to vastly outperform the brain-dead Apple algorithm.

(And the real moral of the story is -- don't set your cache any higher
than 128K, no matter how much RAM you have.)