AcoSail/kernel_optimize_test
8
0
Fork 0
forked from luck/tmp_suning_uos_patched
Code Pull Requests Activity

ipv4: Delete routing cache.

Browse Source 
The ipv4 routing cache is non-deterministic, performance wise, and is
subject to reasonably easy to launch denial of service attacks.

The routing cache works great for well behaved traffic, and the world
was a much friendlier place when the tradeoffs that led to the routing
cache's design were considered.

What it boils down to is that the performance of the routing cache is
a product of the traffic patterns seen by a system rather than being a
product of the contents of the routing tables.  The former of which is
controllable by external entitites.

Even for "well behaved" legitimate traffic, high volume sites can see
hit rates in the routing cache of only ~%10.

Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
David S. Miller 2012-07-17 11:00:09 -07:00
parent fa0afcd109
commit 89aef8921b
3 changed files with 13 additions and 933 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

1
include/net/route.h
View File

@ -109,7 +109,6 @@ extern struct ip_rt_acct __percpu *ip_rt_acct;
struct in_device;
extern int ip_rt_init(void);
extern void rt_cache_flush(struct net *net, int how);
extern void rt_cache_flush_batch(struct net *net);
extern struct rtable *__ip_route_output_key(struct net *, struct flowi4 *flp);
extern struct rtable *ip_route_output_flow(struct net *, struct flowi4 *flp,
struct sock *sk);

5
net/ipv4/fib_frontend.c
View File

@ -1072,11 +1072,6 @@ static int fib_netdev_event(struct notifier_block *this, unsigned long event, vo
rt_cache_flush(dev_net(dev), 0);
break;
case NETDEV_UNREGISTER_BATCH:
/* The batch unregister is only called on the first
* device in the list of devices being unregistered.
* Therefore we should not pass dev_net(dev) in here.
*/
rt_cache_flush_batch(NULL);
break;
}
return NOTIFY_DONE;

940
net/ipv4/route.c
View File

File diff suppressed because it is too large Load Diff