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  1. 30 1月, 2009 10 次提交
  3. 27 1月, 2009 3 次提交
  5. 23 1月, 2009 7 次提交
  7. 22 1月, 2009 3 次提交
    • E
      inet: Allowing more than 64k connections and heavily optimize bind(0) time. · a9d8f911
      由 Evgeniy Polyakov 提交于 
      With simple extension to the binding mechanism, which allows to bind more
than 64k sockets (or smaller amount, depending on sysctl parameters),
we have to traverse the whole bind hash table to find out empty bucket.
And while it is not a problem for example for 32k connections, bind()
completion time grows exponentially (since after each successful binding
we have to traverse one bucket more to find empty one) even if we start
each time from random offset inside the hash table.

So, when hash table is full, and we want to add another socket, we have
to traverse the whole table no matter what, so effectivelly this will be
the worst case performance and it will be constant.

Attached picture shows bind() time depending on number of already bound
sockets.

Green area corresponds to the usual binding to zero port process, which
turns on kernel port selection as described above. Red area is the bind
process, when number of reuse-bound sockets is not limited by 64k (or
sysctl parameters). The same exponential growth (hidden by the green
area) before number of ports reaches sysctl limit.

At this time bind hash table has exactly one reuse-enbaled socket in a
bucket, but it is possible that they have different addresses. Actually
kernel selects the first port to try randomly, so at the beginning bind
will take roughly constant time, but with time number of port to check
after random start will increase. And that will have exponential growth,
but because of above random selection, not every next port selection
will necessary take longer time than previous. So we have to consider
the area below in the graph (if you could zoom it, you could find, that
there are many different times placed there), so area can hide another.

Blue area corresponds to the port selection optimization.

This is rather simple design approach: hashtable now maintains (unprecise
and racely updated) number of currently bound sockets, and when number
of such sockets becomes greater than predefined value (I use maximum
port range defined by sysctls), we stop traversing the whole bind hash
table and just stop at first matching bucket after random start. Above
limit roughly corresponds to the case, when bind hash table is full and
we turned on mechanism of allowing to bind more reuse-enabled sockets,
so it does not change behaviour of other sockets.
Signed-off-by: NEvgeniy Polyakov <zbr@ioremap.net>
Tested-by: NDenys Fedoryschenko <denys@visp.net.lb>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      a9d8f911
    • S
      netrom: convert to internal net_device_stats · b51414b6
      由 Stephen Hemminger 提交于 
      Signed-off-by: NStephen Hemminger <shemminger@vyatta.com>
Acked-by: NRalf Baechle <ralf@linux-mips.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      b51414b6
    • S
      clip: convert to internal network_device_stats · 1a6afe8a
      由 Stephen Hemminger 提交于 
      Signed-off-by: NStephen Hemminger <shemminger@vyatta.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      1a6afe8a
  9. 17 1月, 2009 1 次提交
  11. 11 1月, 2009 1 次提交
  13. 09 1月, 2009 2 次提交
  15. 08 1月, 2009 1 次提交
  17. 07 1月, 2009 2 次提交
  19. 05 1月, 2009 1 次提交
    • D
      ipv6: Fix sporadic sendmsg -EINVAL when sending to multicast groups. · 14deae41
      由 David S. Miller 提交于 
      Thanks to excellent diagnosis by Eduard Guzovsky.

The core problem is that on a network with lots of active
multicast traffic, the neighbour cache can fill up.  If
we try to allocate a new route and thus neighbour cache
entry, the bog-standard GC attempt the neighbour layer does
in ineffective because route entries hold a reference
to the existing neighbour entries and GC can only liberate
entries with no references.

IPV4 already has a way to handle this, by doing a route cache
GC in such situations (when neigh attach returns -ENOBUFS).

So simply mimick this on the ipv6 side.
Tested-by: NEduard Guzovsky <eguzovsky@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      14deae41
  21. 01 1月, 2009 1 次提交
  23. 26 12月, 2008 2 次提交
  25. 25 12月, 2008 1 次提交
  27. 22 12月, 2008 1 次提交
  29. 20 12月, 2008 4 次提交