Re: [PATCH] 2.2.17pre7 VM enhancement Re: I/O performance on
From: Rik van Riel <hidden>
Date: 2000-07-17 17:02:09
On Mon, 17 Jul 2000, Manfred Spraul wrote:
Rik van Riel wrote:quoted
Actually, FreeBSD has a special case in the page fault code for sequential accesses and I believe we must have that too.Where is that code?
It's in vm_fault.c, look for the readaround code.
quoted
Both LRU and LFU break down on linear accesses to an array that doesn't fit in memory. In that case you really want MRU replacement, with some simple code that "detects the window size" you need to keep in memory. This seems to be the only way to get any speedup on such programs when you increase memory size to something which is still smaller than the total program size.Do you have an idea how to detect that situation?
I've got some ideas, but they need to be polished a bit
before I can put them into code. I'll probably do this
at OLS...
regards,
Rik
--
"What you're running that piece of shit Gnome?!?!"
-- Miguel de Icaza, UKUUG 2000
http://www.conectiva.com/ http://www.surriel.com/
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org. For more info on Linux MM,
see: http://www.linux.eu.org/Linux-MM/