Subject: Re: Virtual Memory Subsystem
To: Jukka Marin <>
From: Curt Sampson <>
List: port-i386
Date: 11/26/1996 11:49:57
On Tue, 26 Nov 1996, Jukka Marin wrote:

> But still, it would help with mmap() and make disk IO faster on machines
> with lots of RAM...

Well, it depends on the workload, actually. From what I've read of
the merged VM/cache systems (and I am, admittedly not the sort of
expert that John Dyson is on these matters--so if he disagrees,
he's right :-)) huge amounts of linear disk I/O can start chucking
lesser used processes out of memory, when the lesser used processes
will run again and the disk I/O won't happen again.

I've heard from people who've seen this sort of thing actually
happen on SunOS machines.


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