Newsgroups: comp.arch
Path: utzoo!henry
From: henry@utzoo.uucp (Henry Spencer)
Subject: Re: Do RISC Compilers Consider Multipro
Message-ID: <1988May8.022544.17676@utzoo.uucp>
Organization: U of Toronto Zoology
References: <620@speedy.mcnc.org>, <28200140@urbsdc>
Date: Sun, 8 May 88 02:25:44 GMT

> Agree with your concern - many RISCs, especially those with register 
> windows, have greatly increased context switch penalties.

However, they may be able to get more done between context switches, by
virtue of the extra performance bought by that extra state.  This may well
end up reducing the average degree of multiprogramming and the number of
context switches.  Context-switch penalty BY ITSELF is significant only
if you're interested in latency to the near-total exclusion of throughput.
-- 
NASA is to spaceflight as            |  Henry Spencer @ U of Toronto Zoology
the Post Office is to mail.          | {ihnp4,decvax,uunet!mnetor}!utzoo!henry