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| author | David S. Miller <davem@davemloft.net> | 2015-03-06 22:57:46 +0300 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2015-03-06 22:57:46 +0300 |
| commit | f0fdc80bd9ced4de3eb165c9c408e83713a71104 (patch) | |
| tree | edd39a71398f8639e3166dd64805399c5a8cec11 /include | |
| parent | aaa4e70404c7b38a8792dc69af54afd7218b2ec0 (diff) | |
| parent | fab42760843734a82b6b2d1241ca44f375a686eb (diff) | |
| download | linux-f0fdc80bd9ced4de3eb165c9c408e83713a71104.tar.xz | |
Merge branch 'pmtu-probe'
Fan Du says:
====================
Improvements for TCP PMTU
This patchset performs some improvements and enhancement
for current TCP PMTU as per RFC4821 with the aim to find
optimal mms size quickly, and also be adaptive to route
changes like enlarged path MTU. Then TCP PMTU could be
used to probe a effective pmtu in absence of ICMP message
for tunnels(e.g. vxlan) across different networking stack.
Patch1/4: Set probe mss base to 1024 Bytes per RFC4821
Patch2/4: Do not double probe_size for each probing,
use a simple binary search to gain maximum performance.
mss for next probing.
Patch3/4: Create a probe timer to detect enlarged path MTU.
Patch4/4: Update ip-sysctl.txt for new sysctl knobs.
Changelog:
v5:
- Zero probe_size before resetting search range.
- Update ip-sysctl.txt for new sysctl knobs.
v4:
- Convert probe_size to mss, not directly from search_low/high
- Clamp probe_threshold
- Don't adjust search_high in blackhole probe, so drop orignal patch3
v3:
- Update commit message for patch2
- Fix pseudo timer delta calculation in patch4
v2:
- Introduce sysctl_tcp_probe_threshold to control when
probing will stop, as suggested by John Heffner.
- Add patch3 to shrink current mss value for search low boundary.
- Drop cannonical timer usages, implements pseudo timer based on
32bits jiffies tcp_time_stamp, as suggested by Eric Dumazet.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'include')
| -rw-r--r-- | include/net/inet_connection_sock.h | 2 | ||||
| -rw-r--r-- | include/net/netns/ipv4.h | 2 | ||||
| -rw-r--r-- | include/net/tcp.h | 8 |
3 files changed, 11 insertions, 1 deletions
diff --git a/include/net/inet_connection_sock.h b/include/net/inet_connection_sock.h index 5976bdecf58b..b9a6b0a94cc6 100644 --- a/include/net/inet_connection_sock.h +++ b/include/net/inet_connection_sock.h @@ -126,6 +126,8 @@ struct inet_connection_sock { /* Information on the current probe. */ int probe_size; + + u32 probe_timestamp; } icsk_mtup; u32 icsk_ca_priv[16]; u32 icsk_user_timeout; diff --git a/include/net/netns/ipv4.h b/include/net/netns/ipv4.h index 1085e12f940f..8f3a1a1a5a94 100644 --- a/include/net/netns/ipv4.h +++ b/include/net/netns/ipv4.h @@ -87,6 +87,8 @@ struct netns_ipv4 { int sysctl_tcp_fwmark_accept; int sysctl_tcp_mtu_probing; int sysctl_tcp_base_mss; + int sysctl_tcp_probe_threshold; + u32 sysctl_tcp_probe_interval; struct ping_group_range ping_group_range; diff --git a/include/net/tcp.h b/include/net/tcp.h index f87599d5af82..2e11e38205c2 100644 --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -65,7 +65,13 @@ void tcp_time_wait(struct sock *sk, int state, int timeo); #define TCP_MIN_MSS 88U /* The least MTU to use for probing */ -#define TCP_BASE_MSS 512 +#define TCP_BASE_MSS 1024 + +/* probing interval, default to 10 minutes as per RFC4821 */ +#define TCP_PROBE_INTERVAL 600 + +/* 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 |