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From: vossron@Apple.COM (Ronald N. Voss)
Newsgroups: comp.sys.mac.system
Subject: Re: RAM Cache
Keywords: best size
Message-ID: <41579@apple.Apple.COM>
Date: 4 Jun 90 16:27:47 GMT
References: <732@usage.csd.unsw.oz.au>
Organization: Apple Computer Inc., Cupertino, CA
Lines: 21

pem@usage.csd.unsw.oz.au (Peter E. Middleton) writes:

>        I am curious to know what is the best size for the RAM cache.
>	I realise that the amount of RAM makes a difference, but assuming
>adequate RAM how do things like the number of volumes, their types,
>the number of open files (is this applicable?) etc affect the
>best choice? Is there a point at which cache managment overhead
>exceeds any gains?

IMHO, there is no best or right size.  It depends.  It depends on how
much memory you have and what you're doing.  It depends on what you
want to keep in the cache.  For example, if you're running uniFinder,
you might want to allocate enough to keep Finder resident.  If you
search for files on your disk often, you might want to allocate enough
to get through a complete Find File without tickling the disk.  For
those who don't have or can't see the disk access LED, I find InUse
indispensible.  As far as overhead exceeding gains, it's theoretically
possible, but you have to get into seek times, rotational latency, CPU
and memory speed to find out.
-- 
Ron Voss          Apple Computer         I speak only for myself.