On Mon, Feb 6, 2012 at 2:19 PM, Jan Safranek <jsafr...@redhat.com> wrote:
> On 02/04/2012 05:34 AM, Balbir Singh wrote: > > On Fri, Feb 3, 2012 at 7:29 PM, Jan Safranek <jsafr...@redhat.com> > wrote: > > > >> On 02/01/2012 02:02 PM, Martin wrote: > >>> Hello, > >>> > >>> hopfully this is the right place for such a question: > >>> > >>> I'm not sure when a modification of an existing cgroup takes effect. > >>> There's a cgroup which has running processes in it. During runtime its > >>> necessary to adapt a few cgroup parameters by using the > >>> cgroup_modify_cgroup() function. Now the point of interest is do > changes > >>> affect running task directly. (i.e. by setting a reduced value for > >>> "memory.limit_in_bytes" are tasks forced to reduce mem. consume or are > >>> already allocated / running events not affected?) . Do such changes > >> affect > >>> only future consume (malloc)? > >> > >> This is more or less question to kernel guys... Libcgroup only writes > >> the parameter to kernel cgroup subsystem and honestly I don't know how > >> memory.limit_in_bytes are enforced. Check kernel documentation at > >> http://kernel.org/doc/Documentation/cgroups/memory.txt and ask a > >> kernelist if still not sure. > >> > > > > The effect should be immediate - as soon as the new value is written to > the > > file. We have notifiers that tell us the file has changed and we act on > it > > Yes, you act immediately, but how? Do you run OOM killer? Or just deny > future allocations? > > Jan, We do a reclaim if the size is reduced for example (limit_in_bytes is written to and the new value is lesser). For a higher value, we don't do much, but internal house keeping to allow higher use of memory Balbir ------------------------------------------------------------------------------ Try before you buy = See our experts in action! The most comprehensive online learning library for Microsoft developers is just $99.99! Visual Studio, SharePoint, SQL - plus HTML5, CSS3, MVC3, Metro Style Apps, more. Free future releases when you subscribe now! http://p.sf.net/sfu/learndevnow-dev2 _______________________________________________ Libcg-devel mailing list Libcg-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/libcg-devel
