From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from max.fys.ruu.nl (max.fys.ruu.nl [131.211.32.73]) by kvack.org (8.8.7/8.8.7) with ESMTP id TAA20106 for ; Thu, 26 Feb 1998 19:24:55 -0500 Date: Fri, 27 Feb 1998 00:34:59 +0100 (MET) From: Rik van Riel Reply-To: Rik van Riel Subject: Re: Fairness in love and swapping In-Reply-To: <199802262244.WAA03924@dax.dcs.ed.ac.uk> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org To: "Stephen C. Tweedie" Cc: "Dr. Werner Fink" , torvalds@transmeta.com, nahshon@actcom.co.il, alan@lxorguk.ukuu.org.uk, paubert@iram.es, mingo@chiara.csoma.elte.hu, linux-mm@kvack.org List-ID: On Thu, 26 Feb 1998, Stephen C. Tweedie wrote: > > Without my mmap-age patch, page cache pages aren't aged > > at all... They're just freed whenever they weren't referenced > > since the last scan. The PAGE_AGE_VALUE is quite useless IMO > > (but I could be wrong, Stephen?). > > They _are_ useful for mapped images such as binaries (which are swapped > out by vmscan.c, not filemap.c), but not for otherwise unused, pure > cached pages. AFAIK, mapped images aren't part of a proces' RSS, but are page-cached (page->inode type of RSS). And swapping of those vma's _is_ done in shrink_mmap() in filemap.c. Furthermore, it's quite useful if your read-ahead pages stay in memory for a while so you don't read them two or even three times before they're actually used. But if I've overlooked something, I'd really like to hear about it... A bit of a clue never hurts when coding up new patches :-) Rik. +-----------------------------+------------------------------+ | For Linux mm-patches, go to | "I'm busy managing memory.." | | my homepage (via LinuxHQ). | H.H.vanRiel@fys.ruu.nl | | ...submissions welcome... | http://www.fys.ruu.nl/~riel/ | +-----------------------------+------------------------------+