diff options
| author | Eric Dumazet <eric.dumazet@gmail.com> | 2011-06-08 17:35:34 +0400 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2011-06-09 04:05:30 +0400 |
| commit | 4b9d9be839fdb7dcd7ce7619a623fd9015a50cda (patch) | |
| tree | bd1827203efe27578b783c30b0ff5e2d4966b26a /include/net/inetpeer.h | |
| parent | 9ad7c049f0f79c418e293b1b68cf10d68f54fcdb (diff) | |
| download | linux-4b9d9be839fdb7dcd7ce7619a623fd9015a50cda.tar.xz | |
inetpeer: remove unused list
Andi Kleen and Tim Chen reported huge contention on inetpeer
unused_peers.lock, on memcached workload on a 40 core machine, with
disabled route cache.
It appears we constantly flip peers refcnt between 0 and 1 values, and
we must insert/remove peers from unused_peers.list, holding a contended
spinlock.
Remove this list completely and perform a garbage collection on-the-fly,
at lookup time, using the expired nodes we met during the tree
traversal.
This removes a lot of code, makes locking more standard, and obsoletes
two sysctls (inet_peer_gc_mintime and inet_peer_gc_maxtime). This also
removes two pointers in inet_peer structure.
There is still a false sharing effect because refcnt is in first cache
line of object [were the links and keys used by lookups are located], we
might move it at the end of inet_peer structure to let this first cache
line mostly read by cpus.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
CC: Andi Kleen <andi@firstfloor.org>
CC: Tim Chen <tim.c.chen@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'include/net/inetpeer.h')
| -rw-r--r-- | include/net/inetpeer.h | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/include/net/inetpeer.h b/include/net/inetpeer.h index 8a159cc3d68b..1f0966f91760 100644 --- a/include/net/inetpeer.h +++ b/include/net/inetpeer.h @@ -32,7 +32,6 @@ struct inet_peer { struct inet_peer __rcu *avl_left, *avl_right; struct inetpeer_addr daddr; __u32 avl_height; - struct list_head unused; __u32 dtime; /* the time of last use of not * referenced entries */ atomic_t refcnt; @@ -56,6 +55,7 @@ struct inet_peer { struct inetpeer_addr_base redirect_learned; }; struct rcu_head rcu; + struct inet_peer *gc_next; }; }; |