From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Tue, 5 Dec 2006 08:17:51 -0800 (PST) From: Linus Torvalds Subject: RE: la la la la ... swappiness In-Reply-To: <200612050641.kB56f7wY018196@ms-smtp-06.texas.rr.com> Message-ID: References: <200612050641.kB56f7wY018196@ms-smtp-06.texas.rr.com> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org Return-Path: To: Aucoin Cc: 'Nick Piggin' , 'Tim Schmielau' , 'Andrew Morton' , clameter@sgi.com, Linux Memory Management List List-ID: On Tue, 5 Dec 2006, Aucoin wrote: > > > Louis, exactly how do you allocate that big 1.6GB shared area? > > Ummm, shm_open, ftruncate, mmap ? Is it a trick question ? The process > responsible for initially setting up the shared area doesn't stay resident. Not a trick question, I just suddenly realized that I really should have expected the SHM pages to show up in the LRU lists (either inactive or active) and shown up as "cached" pages too. Afaik, the SHM routines all end up using the page cache and the LRU for the backing store. But your 1.6GB thing doesn't show up anywhere. (I'm sure it's intentional, and I've just forgotten some detail. We probably remove pages from the LRU lists when they are locked. Anyway, my original point was that since the pages _aren't_ on the LRU lists, the VM really should basically act as if they didn't exist at all, but there are probably things that still base their decisions on the _total_ amount of memory) Linus -- 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-mm.org/ . Don't email: email@kvack.org