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| author | Yuchung Cheng <ycheng@google.com> | 2017-12-12 13:10:40 -0800 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2017-12-13 15:51:12 -0500 |
| commit | 7268586baa530312041e597b518b5c6a05110df1 (patch) | |
| tree | 09075b8fb35fcc5ad90f744345d1582fe7d62f4c /Documentation/networking | |
| parent | 8a83c5d7969b8433584e3cf658a8d76c4dc37f4d (diff) | |
| download | linux-7268586baa530312041e597b518b5c6a05110df1.tar.gz linux-7268586baa530312041e597b518b5c6a05110df1.tar.bz2 linux-7268586baa530312041e597b518b5c6a05110df1.zip | |
tcp: pause Fast Open globally after third consecutive timeout
Prior to this patch, active Fast Open is paused on a specific
destination IP address if the previous connections to the
IP address have experienced recurring timeouts . But recent
experiments by Microsoft (https://goo.gl/cykmn7) and Mozilla
browsers indicate the isssue is often caused by broken middle-boxes
sitting close to the client. Therefore it is much better user
experience if Fast Open is disabled out-right globally to avoid
experiencing further timeouts on connections toward other
destinations.
This patch changes the destination-IP disablement to global
disablement if a connection experiencing recurring timeouts
or aborts due to timeout. Repeated incidents would still
exponentially increase the pause time, starting from an hour.
This is extremely conservative but an unfortunate compromise to
minimize bad experience due to broken middle-boxes.
Reported-by: Dragana Damjanovic <ddamjanovic@mozilla.com>
Reported-by: Patrick McManus <mcmanus@ducksong.com>
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Reviewed-by: Wei Wang <weiwan@google.com>
Reviewed-by: Neal Cardwell <ncardwell@google.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'Documentation/networking')
| -rw-r--r-- | Documentation/networking/ip-sysctl.txt | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/Documentation/networking/ip-sysctl.txt b/Documentation/networking/ip-sysctl.txt index 46c7e1085efc..3f2c40d8e6aa 100644 --- a/Documentation/networking/ip-sysctl.txt +++ b/Documentation/networking/ip-sysctl.txt @@ -606,6 +606,7 @@ tcp_fastopen_blackhole_timeout_sec - INTEGER This time period will grow exponentially when more blackhole issues get detected right after Fastopen is re-enabled and will reset to initial value when the blackhole issue goes away. + 0 to disable the blackhole detection. By default, it is set to 1hr. tcp_syn_retries - INTEGER |