From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Tue, 5 Dec 2006 08:59:14 -0800 From: Andrew Morton Subject: Re: la la la la ... swappiness Message-Id: <20061205085914.b8f7f48d.akpm@osdl.org> In-Reply-To: References: <200612050641.kB56f7wY018196@ms-smtp-06.texas.rr.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: Linus Torvalds Cc: Aucoin , 'Nick Piggin' , 'Tim Schmielau' , clameter@sgi.com, Linux Memory Management List List-ID: On Tue, 5 Dec 2006 08:17:51 -0800 (PST) Linus Torvalds wrote: > > > 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) > Yes, those pages should be on the LRU. I suspect they never got paged in or something. But that would mean they weren't mlocked. Is a mystery. -- 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