From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from dax.scot.redhat.com (sct@dax.scot.redhat.com [195.89.149.242]) by kvack.org (8.8.7/8.8.7) with ESMTP id LAA12043 for ; Thu, 21 Jan 1999 11:51:34 -0500 Date: Thu, 21 Jan 1999 16:50:36 GMT Message-Id: <199901211650.QAA04674@dax.scot.redhat.com> From: "Stephen C. Tweedie" MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Subject: Re: MM deadlock [was: Re: arca-vm-8...] In-Reply-To: <19990114155321.C573@Galois.suse.de> References: <199901132214.WAA07436@dax.scot.redhat.com> <19990114155321.C573@Galois.suse.de> Sender: owner-linux-mm@kvack.org To: "Dr. Werner Fink" Cc: "Stephen C. Tweedie" , Andrea Arcangeli , Rik van Riel , Zlatko Calusic , Linus Torvalds , "Eric W. Biederman" , Savochkin Andrey Vladimirovich , steve@netplus.net, brent verner , "Garst R. Reese" , Kalle Andersson , Ben McCann , Alan Cox , bredelin@ucsd.edu, linux-kernel@vger.rutgers.edu, linux-mm@kvack.org List-ID: Hi, On Thu, 14 Jan 1999 15:53:21 +0100, "Dr. Werner Fink" said: >> There is no aging on the page cache at all other than the PG_referenced >> bit. > I know that most of you do not like aging. Nevertheless, on high stressed > systems with less than 128M you will see a critical point whereas the page > cache and readahead does not avoid that swapin I/O time needed by a program > increases to similar size of the average program time slice. There's no reason why timeslices should have anything to do with swapin IO time; we do not count time spent waiting for IO against the process's allocated timeslice. > What's about a simple aging of program page cluster or better of the > page cache? Increasing the age could be done if and only if the pages > or page clusters swapped in and the program wasn't able to use its > time slice. Decreasing the age could be placed in shrink_mmap(). Page aging dramatically increases the amount of CPU time we spend looking for free pages. The selection of which pages to swap out really shouldn't have anything to do with scheduling of CPU-bound processes (which is the only time where timeslices actually count for anything). --Stephen -- This is a majordomo managed list. To unsubscribe, send a message with the body 'unsubscribe linux-mm me@address' to: majordomo@kvack.org