On Tue 04-09-18 15:59:34, Shuah Khan wrote: [...] > This will support the following workload requirements: > > - reserving one or more NUMA memory nodes for class of critical tasks that > require > guaranteed memory availability. > - isolate memory blocks with a guaranteed exclusive access.
How do you enforce kernel doesn't allocate from those reserved nodes? They will be in a fallback zonelists so once the memory gets used on all other ones then the kernel happily spills over to your reserved node. > NUMA emulation to split the flat machine into "x" number of nodes, combined > with > cpuset cgroup with the following example configuration will make it possible > to > support the above workloads on non-NUMA platforms. > > numa=fake=4 > > cpuset.mems=2 > cpuset.cpus=2 > cpuset.mem_exclusive=1 (enabling exclusive use of the memory nodes by a CPU > set) > cpuset.mem_hardwall=1 (separate the memory nodes that are allocated to > different cgroups) This will only enforce userspace to follow and I strongly suspect that tasks in the root cgroup will be allowed to allocate as well. -- Michal Hocko SUSE Labs
