On Wed 13-10-21 12:42:34, Michal Hocko wrote: > [Cc linux-api] > > On Wed 13-10-21 15:15:39, Aneesh Kumar K.V wrote: > > This mempolicy mode can be used with either the set_mempolicy(2) > > or mbind(2) interfaces. Like the MPOL_PREFERRED interface, it > > allows an application to set a preference node from which the kernel > > will fulfill memory allocation requests. Unlike the MPOL_PREFERRED mode, > > it takes a set of nodes. The nodes in the nodemask are used as fallback > > allocation nodes if memory is not available on the preferred node. > > Unlike MPOL_PREFERRED_MANY, it will not fall back memory allocations > > to all nodes in the system. Like the MPOL_BIND interface, it works over a > > set of nodes and will cause a SIGSEGV or invoke the OOM killer if > > memory is not available on those preferred nodes. > > > > This patch helps applications to hint a memory allocation preference node > > and fallback to _only_ a set of nodes if the memory is not available > > on the preferred node. Fallback allocation is attempted from the node which is > > nearest to the preferred node. > > > > This new memory policy helps applications to have explicit control on slow > > memory allocation and avoids default fallback to slow memory NUMA nodes. > > The difference with MPOL_BIND is the ability to specify a preferred node > > which is the first node in the nodemask argument passed. I am sorry but I do not understand the semantic diffrence from MPOL_BIND. Could you be more specific please? -- Michal Hocko SUSE Labs