Red Hat SummitChapter 28. Profiling memory allocation with numastat
The numastat tool provides detailed statistics on memory allocations within a system, presenting data for each NUMA node individually. This information is valuable for analyzing system memory performance and evaluating the efficacy of various memory policies.
28.1. Default numastat statistics
By default, the numastat tool displays statistics over these categories of data for each NUMA node:
numa_hit- The number of pages that were successfully allocated to this node.
numa_missThe number of pages that were allocated on this node because of low memory on the intended node. Each
numa_missevent has a correspondingnuma_foreignevent on another node.NoteHigh
numa_hitvalues and lownuma_missvalues (relative to each other) indicate optimal performance.numa_foreign-
The number of pages initially intended for this node that were allocated to another node instead. Each
numa_foreignevent has a correspondingnuma_missevent on another node. interleave_hit- The number of interleave policy pages successfully allocated to this node.
local_node- The number of pages successfully allocated on this node by a process on this node.
other_node- The number of pages allocated on this node by a process on another node.
28.2. Viewing memory allocation with numastat
You can view the memory allocation of the system by using the numastat tool.
Prerequisites
You have installed the
numactlpackage.# dnf install numactl
Procedure
View the memory allocation of your system:
$ numastatnode0 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
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