Chapter 30. Profiling memory allocation with numastat
numastat tool, you can display statistics over memory allocations in a system.
numastat tool displays data for each NUMA node separately. You can use this information to investigate memory performance of your system or the effectiveness of different memory policies on your system.
30.1. Default numastat statistics
By default, the
numastat tool displays statistics over these categories of data for each NUMA node:
- The number of pages that were successfully allocated to this node.
The number of pages that were allocated on this node because of low memory on the intended node. Each
numa_missevent has a corresponding
numa_foreignevent on another node.
The number of pages initially intended for this node that were allocated to another node instead. Each
numa_foreignevent has a corresponding
numa_missevent on another node.
- The number of interleave policy pages successfully allocated to this node.
- The number of pages successfully allocated on this node by a process on this node.
- The number of pages allocated on this node by a process on another node.
numa_hit values and low
numa_miss values (relative to each other) indicate optimal performance.
30.2. Viewing memory allocation with numastat
You can view the memory allocation of the system by using the
# yum install numactl
View the memory allocation of your system:
$ numastat node0 node1 numa_hit 76557759 92126519 numa_miss 30772308 30827638 numa_foreign 30827638 30772308 interleave_hit 106507 103832 local_node 76502227 92086995 other_node 30827840 30867162