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| author | Dave Airlie <airlied@redhat.com> | 2026-09-26 07:57:59 +1000 |
|---|---|---|
| committer | Dave Airlie <airlied@redhat.com> | 2026-09-26 07:58:24 +1000 |
| commit | a9ed3aa9b87ee41e8ab3ff471b1331c154767e45 (patch) | |
| tree | cc62d74e0eb4905246978674461e78e2f9df2afd /Documentation/admin-guide/numastat.rst | |
| download | linux-stable-a9ed3aa9b87ee41e8ab3ff471b1331c154767e45.tar.gz linux-stable-a9ed3aa9b87ee41e8ab3ff471b1331c154767e45.zip | |
Merge tag 'drm-misc-fixes-2026-09-24' of https://gitlab.freedesktop.org/drm/misc/kernel into drm-fixesgrafted
A number of fixes:
- bridge:
- samsung-dsim: fix GPIO lifetime
- client: Null pointer dereference fix
- imagination: error handling fix, page handling fix
- nouveau: fix reference leaks, double-frees, out-of-bounds accesses,
use-after-frees, don't reject config without SCDC, a number of
workarounds
- virtio: fix memory leak, reference leaks, null pointer dereference,
add pixel blend mode, cache coherency fix
Signed-off-by: Dave Airlie <airlied@redhat.com>
From: Maxime Ripard <self@mripard.dev>
Link: https://patch.msgid.link/arU22zzqUGDEco1y@houat
Diffstat (limited to 'Documentation/admin-guide/numastat.rst')
| -rw-r--r-- | Documentation/admin-guide/numastat.rst | 55 |
1 files changed, 55 insertions, 0 deletions
diff --git a/Documentation/admin-guide/numastat.rst b/Documentation/admin-guide/numastat.rst new file mode 100644 index 000000000..08ec2c2bd --- /dev/null +++ b/Documentation/admin-guide/numastat.rst @@ -0,0 +1,55 @@ +=============================== +Numa policy hit/miss statistics +=============================== + +/sys/devices/system/node/node*/numastat + +All units are pages. Hugepages have separate counters. + +The numa_hit, numa_miss and numa_foreign counters reflect how well processes +are able to allocate memory from nodes they prefer. If they succeed, numa_hit +is incremented on the preferred node, otherwise numa_foreign is incremented on +the preferred node and numa_miss on the node where allocation succeeded. + +Usually preferred node is the one local to the CPU where the process executes, +but restrictions such as mempolicies can change that, so there are also two +counters based on CPU local node. local_node is similar to numa_hit and is +incremented on allocation from a node by CPU on the same node. other_node is +similar to numa_miss and is incremented on the node where allocation succeeds +from a CPU from a different node. Note there is no counter analogical to +numa_foreign. + +In more detail: + +=============== ============================================================ +numa_hit A process wanted to allocate memory from this node, + and succeeded. + +numa_miss A process wanted to allocate memory from another node, + but ended up with memory from this node. + +numa_foreign A process wanted to allocate on this node, + but ended up with memory from another node. + +local_node A process ran on this node's CPU, + and got memory from this node. + +other_node A process ran on a different node's CPU + and got memory from this node. + +interleave_hit Interleaving wanted to allocate from this node + and succeeded. +=============== ============================================================ + +For easier reading you can use the numastat utility from the numactl package +(http://oss.sgi.com/projects/libnuma/). Note that it only works +well right now on machines with a small number of CPUs. + +Note that on systems with memoryless nodes (where a node has CPUs but no +memory) the numa_hit, numa_miss and numa_foreign statistics can be skewed +heavily. In the current kernel implementation, if a process prefers a +memoryless node (i.e. because it is running on one of its local CPU), the +implementation actually treats one of the nearest nodes with memory as the +preferred node. As a result, such allocation will not increase the numa_foreign +counter on the memoryless node, and will skew the numa_hit, numa_miss and +numa_foreign statistics of the nearest node. |
