Path: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!mailrus!tut.cis.ohio-state.edu!brutus.cs.uiuc.edu!ginosko!uunet!cbmvax!daveh
From: daveh@cbmvax.UUCP (Dave Haynie)
Newsgroups: comp.arch
Subject: Re: SRAM vs. DRAM, 33MHz 386 UNIX-PC
Message-ID: <7906@cbmvax.UUCP>
Date: 14 Sep 89 13:44:28 GMT
References: <124529@sun.Eng.Sun.COM>
Organization: Commodore Technology, West Chester, PA
Lines: 17

in article <124529@sun.Eng.Sun.COM>, katin@skylark.Sun.COM (Neil Katin) says:

> You *do* need to flush the on-chip 68030 cache when doing task switches
> because it is a virtual cache.  You probably don't need to flush any
> off-chip 68030 caches because they are physical caches (since the 68030
> has an on-chip MMU).

Undoubtedly why Motorola went to physical caches on the 68040.  The main
problem with physical cache, of course, is speed, but they apparently got
that licked as of the 88k system.  You rarely have a choice with off-chip
caches -- they tend to be physical, slow, and/or expensive.

> Neil Katin
-- 
Dave Haynie Commodore-Amiga (Systems Engineering) "The Crew That Never Rests"
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