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From: Charles Forsyth <forsyth@terzarima.net>
To: 9fans@9fans.net
Subject: Re: [9fans] gar nix!
Date: Sat, 17 Sep 2011 08:35:29 +0100	[thread overview]
Message-ID: <fffef2f8604a785328f4b888a62eb565@terzarima.net> (raw)
In-Reply-To: <CAJQxxw=tqoFB-Y9PXUNdd5Zvzijo-jPAYeb+jaGk_N74tivM-w@mail.gmail.com>

the trouble with the zeroing pages scheme, which has been done before
(eg, having the process with least priority top up the memory), is that
it was great when the system wasn't under load, just fine under increased
load, but eventually, when you most want your cycles, you're back
in the original situation. if you were able to hold usage below that
level, it still worked against keeping more useful data cached in that memory.
(in effect, you had a cache of zeroes.) in a similar way, there might be more useful things
to do with your DMA cycles, which cost something too, and there are implications for power.

the maths behind Working Set hasn't gone away just because the parameters got bigger.
otherwise, it would never have been true.



  reply	other threads:[~2011-09-17  7:35 UTC|newest]

Thread overview: 27+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-09-16  1:19 erik quanstrom
2011-09-16  5:44 ` Noah Evans
2011-09-17 19:41   ` erik quanstrom
2011-09-17 20:03     ` Noah Evans
2011-09-16  5:56 ` ron minnich
     [not found] ` <CAP6exYLuD6ZeOwCfY9TcgSWEYp-2QH-7qUO713GL0cravJ2FzA@mail.gmail.c>
2011-09-16  6:46   ` erik quanstrom
2011-09-16  7:02     ` Nemo
2011-09-16  7:52     ` dexen deVries
2011-09-16 13:36     ` Charles Forsyth
2011-09-16 14:39     ` ron minnich
     [not found]     ` <CAP6exYLy6sicg42A+7D=bmpWtv=p_an3c5=OQw9YB2oxPXhR2A@mail.gmail.c>
2011-09-16 14:57       ` erik quanstrom
2011-09-16 15:28         ` ron minnich
2011-09-16 15:31           ` Francisco J Ballesteros
     [not found]           ` <CA+N-5bbt92zqNpt0KW4prykyTxjYNHJJ7LuUCj4n3EACyC5GvQ@mail.gmail.c>
2011-09-16 15:33             ` erik quanstrom
2011-09-16 15:36               ` Francisco J Ballesteros
2011-09-16 15:44                 ` ron minnich
2011-09-16 16:07                   ` Francisco J Ballesteros
     [not found]               ` <CA+N-5bYJ1VBpqQENUy5fZirE_Joa9E6RE8rJbvaFwh065zd2TA@mail.gmail.c>
2011-09-16 15:37                 ` erik quanstrom
2011-09-16 18:24     ` ron minnich
2011-09-16 22:23       ` Charles Forsyth
2011-09-16 22:27         ` erik quanstrom
2011-09-17  3:39           ` Bruce Ellis
2011-09-17  7:35             ` Charles Forsyth [this message]
2011-09-17  7:44           ` Charles Forsyth
2011-09-17  8:45             ` Charles Forsyth
     [not found]     ` <CAP6exYK+aoYcaC+LLo4XdPmZ1jvPQ0dAgZuUkmX7_xZQ+h3+gQ@mail.gmail.c>
2011-09-16 18:32       ` erik quanstrom
2011-09-16 18:44         ` Francisco J Ballesteros

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