[PATCH net-next v2] docs: net: document neigh gc_stale_time sysctl
From: Gabriel Goller <hidden>
Date: 2026-02-23 10:13:04
Also in:
linux-doc, lkml
Subsystem:
documentation, networking [general], the rest · Maintainers:
Jonathan Corbet, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
Add missing documentation for a neighbor table garbage collector sysctl parameter in ip-sysctl.rst: neigh/default/gc_stale_time: controls how long an unused neighbor entry is kept before becoming eligible for garbage collection (default: 60 seconds) Signed-off-by: Gabriel Goller <redacted> --- Changelog: v1: * removed documentation for gc_interval, as that sysctl is not used anymore and doesn't do anything. * mention gc_stale_time only being used when we have more than gc_thresh1 neighbors. Documentation/networking/ip-sysctl.rst | 11 +++++++++++ 1 file changed, 11 insertions(+)
diff --git a/Documentation/networking/ip-sysctl.rst b/Documentation/networking/ip-sysctl.rst
index 28c7e4f5ecf9..85fda3759534 100644
--- a/Documentation/networking/ip-sysctl.rst
+++ b/Documentation/networking/ip-sysctl.rst@@ -202,6 +202,17 @@ neigh/default/gc_thresh3 - INTEGER Default: 1024 +neigh/default/gc_stale_time - INTEGER + Determines how long a neighbor entry can remain unused before it is + considered stale and eligible for garbage collection. Entries that have + not been used for longer than this time will be removed by the garbage + collector, unless they have active references, are marked as PERMANENT, + or carry the NTF_EXT_LEARNED or NTF_EXT_VALIDATED flag. Stale entries + are only removed by the periodic GC when there are at least gc_thresh1 + neighbors in the table. + + Default: 60 seconds + neigh/default/unres_qlen_bytes - INTEGER The maximum number of bytes which may be used by packets queued for each unresolved address by other network layers.
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2.47.3