diff options
author | Fan Du <fan.du@intel.com> | 2015-03-06 11:18:23 +0800 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2015-03-06 14:57:41 -0500 |
commit | 6b58e0a5f32dedb609438bb9c9c82aa6e23381f2 (patch) | |
tree | dcfd707a04fd8295b1384cc18fc60addf22ae23a /include/net/tcp.h | |
parent | dcd8fb8533ceb493146ce030d15f7965b82d0c27 (diff) | |
download | lwn-6b58e0a5f32dedb609438bb9c9c82aa6e23381f2.tar.gz lwn-6b58e0a5f32dedb609438bb9c9c82aa6e23381f2.zip |
ipv4: Use binary search to choose tcp PMTU probe_size
Current probe_size is chosen by doubling mss_cache,
the probing process will end shortly with a sub-optimal
mss size, and the link mtu will not be taken full
advantage of, in return, this will make user to tweak
tcp_base_mss with care.
Use binary search to choose probe_size in a fine
granularity manner, an optimal mss will be found
to boost performance as its maxmium.
In addition, introduce a sysctl_tcp_probe_threshold
to control when probing will stop in respect to
the width of search range.
Test env:
Docker instance with vxlan encapuslation(82599EB)
iperf -c 10.0.0.24 -t 60
before this patch:
1.26 Gbits/sec
After this patch: increase 26%
1.59 Gbits/sec
Signed-off-by: Fan Du <fan.du@intel.com>
Acked-by: John Heffner <johnwheffner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'include/net/tcp.h')
-rw-r--r-- | include/net/tcp.h | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/include/net/tcp.h b/include/net/tcp.h index 834089b0cffc..1ad82e334e27 100644 --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -67,6 +67,9 @@ void tcp_time_wait(struct sock *sk, int state, int timeo); /* The least MTU to use for probing */ #define TCP_BASE_MSS 1024 +/* Specify interval when tcp mtu probing will stop */ +#define TCP_PROBE_THRESHOLD 8 + /* After receiving this amount of duplicate ACKs fast retransmit starts. */ #define TCP_FASTRETRANS_THRESH 3 |