linux-stable/Documentation/admin-guide/sysctl
Adam Li 12a686c2e7 net: make SK_MEMORY_PCPU_RESERV tunable
This patch adds /proc/sys/net/core/mem_pcpu_rsv sysctl file,
to make SK_MEMORY_PCPU_RESERV tunable.

Commit 3cd3399dd7 ("net: implement per-cpu reserves for
memory_allocated") introduced per-cpu forward alloc cache:

"Implement a per-cpu cache of +1/-1 MB, to reduce number
of changes to sk->sk_prot->memory_allocated, which
would otherwise be cause of false sharing."

sk_prot->memory_allocated points to global atomic variable:
atomic_long_t tcp_memory_allocated ____cacheline_aligned_in_smp;

If increasing the per-cpu cache size from 1MB to e.g. 16MB,
changes to sk->sk_prot->memory_allocated can be further reduced.
Performance may be improved on system with many cores.

Signed-off-by: Adam Li <adamli@os.amperecomputing.com>
Reviewed-by: Christoph Lameter (Ampere) <cl@linux.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2024-02-28 09:23:08 +00:00
..
abi.rst docs: admin-guide: sysctl: avoid using ReST :doc:`foo` markup 2021-06-17 13:24:36 -06:00
fs.rst docs: admin-guide: sysctl: fix details of struct dentry_stat_t 2023-10-03 09:25:55 -06:00
index.rst
kernel.rst asm-generic updates for v6.7 2023-11-01 15:28:33 -10:00
net.rst net: make SK_MEMORY_PCPU_RESERV tunable 2024-02-28 09:23:08 +00:00
sunrpc.rst
user.rst
vm.rst docs: mm: fix vm overcommit documentation for OVERCOMMIT_GUESS 2023-10-10 13:35:55 -06:00