NetNews Usenet Archive 1992 #19/NN_1992_19.iso/spool/comp/sys/mac/hardware/16392

Text File | 1992-09-02 | 1.7 KB | 44 lines

Newsgroups: comp.sys.mac.hardware
Path: sparky!uunet!wupost!uwm.edu!zazen!doug.cae.wisc.edu!neuro!jimy
From: [e-mail] (Jim K. H. Yu)
Subject: Mac IIsi, RAM and cache
Organization: Univ. of Wisconsin-Madison; Electrical & Computer Engineering
Date: 2 Sep 92 13:58:13 CDT
Message-ID: <[e-mail]>
Sender: Jim K. H. Yu
Lines: 33

I use a Mac IIsi with 17MB RAM and System 7.
That is plenty of RAM for my application (at least for now)  :)

Thus, I'm interested in effective ways to use part of that RAM to boost
the Mac's speed, and not only my ego everytime I open the "About this Macintosh..."
box and see a huge amount of available RAM.

To begin with, I could increase the cache size to, say, 2MB.
That would definetely solve the bottle-neck created by the built-in video.
However, too big a cache may not improve the hit ratio and can
even slow down the Mac (cache management overhead increases with
cache size).

Alternatively, I could create a RAM disk and put the whole system and
finder there.
The question is: Does anyone know what kind of cache the Memory
control panel creates?
In other words, If it's a *data cache* for the HD, then it's existence is still
necessary, even with a RAM disk.
However, if it's an *instruction cache*, then is it correct to assume that
running the whole system from a RAM disk is equivalent to 100% hit ratio,
and therefore, I can turn the cache to the minimum size and save 2MB for other use?

If I buy a RAM card, what would be the best settings for the cache?
Would a RAM disk still be effective?

Jim


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Jim K. H. Yu
[e-mail]