On Tue, 30 Mar 2010 10:30:50 +0530 Balbir Singh <balbir@xxxxxxxxxxxxxxxxxx> wrote: > * KAMEZAWA Hiroyuki <kamezawa.hiroyu@xxxxxxxxxxxxxx> [2010-03-30 13:51:59]: > > > > Considering shared library which has only one user, moving MAP_SHARED makes sense. > > > > Unfortunately, there are people who creates their own shared library just for > > > > their private dlopen() etc. (shared library for private use...) > > > > > > > > So, I think moving MAP_SHARED files makes sense. > > > > > > IIRC, the libraries are loaded with MAP_PRIVATE and MAP_SHARED is not > set. > Ah, yes. I was wrong. But changing handling of MAP_SHARED/MAP_PRIVATE is not good. It will give much confusion to users. > > > Thank you for your explanations. > > > I'll update my patches to allow to move MAP_SHARED(but page_mapcount() == 1) > > > file caches, and resend. > > > > > > > Hmm, considering again...current summary is following...right ? > > > > - If page is an anon, it's not moved if page_mapcount() > 2. > > - If page is a page cache, it's not moved if page_mapcount() > 2. > > - If page is a shmem, it's not moved regardless of mapcount. > > - If pte is swap, it's not moved refcnt > 2. > > > > I think following is straightforward and simple. > > > > - If page is an anon or swap of anon, it's not moved if referer > 2. > > What is referer in this context? The cgroup refering to the page? > page_mapcount(page) + refcnt_to_swap_entry(ent.val) Bye. -Kame > > (i.e. inherited from it's parent) > > - If page is file,shmem or swap of shmem, it's moved regardless of referer. > > But pages only under "from" memcg can be moved. > > > > I doubt adding too much speciality to shmem is not good. > > > > Yep, I tend to agree, but I need to take a closer look again at the > patches. > > -- > Three Cheers, > Balbir > -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxxx For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>