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From: johns@hpcuhe.cup.hp.com (John Shelton)
Newsgroups: comp.sys.mac.hardware
Subject: Re: IIsi RAM cache setting, performance...
Message-ID: <31570001@hpcuhe.cup.hp.com>
Date: 13 Jun 91 16:20:13 GMT
References: <1991Jun11.161138.31376@kuhub.cc.ukans.edu>
Organization: Hewlett Packard, Cupertino
Lines: 17

> In 256-color mode, the IIsi reserves 256k for video RAM.  The high (or low,
> whichever it is) 1MB of RAM (where the video is) is, for some reason, slow.
> When code is loaded into that memory bank, such as the Finder, a program,
> whatever, the speed slows down.
> 
> However, the disk cache just happens to use that memory.  1MB - 256K = 768k,
> so that is the setting you should use.  While I have not benchmarked the
> speed improvement, it is enough that I now leave my IIsi in 256-color mode
> in System 7, whereas it used to be in 16-color mode in System 6.0.7.
> 
> Good luck! --Erik

So why is 256-color mode slower than 16-color mode, then?  It seems that
16-color mode would reserve less memory, making it more likely that you
program would be running out of the slow memory.

- John