Commit 40ad0a52 authored by Antoine Tenart's avatar Antoine Tenart Committed by Jakub Kicinski
Browse files

Documentation: add a description for net.core.high_order_alloc_disable 



A description is missing for the net.core.high_order_alloc_disable
option in admin-guide/sysctl/net.rst ; add it. The above sysctl option
was introduced by commit ce27ec60 ("net: add high_order_alloc_disable
sysctl/static key").

Thanks to Eric for running again the benchmark cited in the above
commit, showing this knob is now mostly of historical importance.

Signed-off-by: default avatarAntoine Tenart <atenart@kernel.org>
Reviewed-by: default avatarEric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20220707080245.180525-1-atenart@kernel.org


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent 5b47d236

Documentation/admin-guide/sysctl/net.rst

+12 −0
Original line number Diff line number Diff line
@@ -391,6 +391,18 @@ GRO has decided not to coalesce, it is placed on a per-NAPI list. This 
list is then passed to the stack when the number of segments reaches the

gro_normal_batch limit.



high_order_alloc_disable

------------------------



By default the allocator for page frags tries to use high order pages (order-3

on x86). While the default behavior gives good results in most cases, some users

might have hit a contention in page allocations/freeing. This was especially

true on older kernels (< 5.14) when high-order pages were not stored on per-cpu

lists. This allows to opt-in for order-0 allocation instead but is now mostly of

historical importance.



Default: 0



2. /proc/sys/net/unix - Parameters for Unix domain sockets

----------------------------------------------------------