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From: dce@Solbourne.COM (David Elliott)
Newsgroups: comp.unix.wizards
Subject: GNU OS suggestion -- memory "advice"
Message-ID: <1343@marvin.Solbourne.COM>
Date: 4 Jun 89 03:27:33 GMT
Reply-To: dce@Solbourne.com (David Elliott)
Organization: Solbourne Computer Inc., Longmont, Colorado
Lines: 22

One of the more interesting areas I've had discussions with people
about is the idea of being able to advise the system on how memory will
be used.

Programmers can often predict what areas of a program or chunks of
data space are going to be used more often than others, yet there
is generally no way for the programmer to say that a chunk of code
is or is not needed often, or is only called at a point at which speed
is not critical.

In one case, a developer described a case in which a large array was
being scanned a number of times in both row-major and column-major
order.  He noticed that the slowdown came in the latter case since
the OS was paging his data in an inefficient manner.

Some of the improvements are not dependent upon the OS so much.  I
know that the folks at MIPS developed a program that would reorganize
code for maximum cache speed.

-- 
David Elliott		dce@Solbourne.COM
			...!{boulder,nbires,sun}!stan!dce