From: Jesper Dangaard Brouer <brouer@redhat.com>
To: Eric Dumazet <eric.dumazet@gmail.com>
Cc: "David S. Miller" <davem@davemloft.net>,
Florian Westphal <fw@strlen.de>,
netdev@vger.kernel.org, Pablo Neira Ayuso <pablo@netfilter.org>,
Thomas Graf <tgraf@suug.ch>, Cong Wang <amwang@redhat.com>,
Patrick McHardy <kaber@trash.net>,
"Paul E. McKenney" <paulmck@linux.vnet.ibm.com>,
Herbert Xu <herbert@gondor.hengli.com.au>
Subject: Re: [net-next PATCH V2 8/9] net: frag queue locking per hash bucket
Date: Fri, 30 Nov 2012 13:55:32 +0100 [thread overview]
Message-ID: <1354280132.11754.435.camel@localhost> (raw)
In-Reply-To: <1354208920.14302.1907.camel@edumazet-glaptop>
On Thu, 2012-11-29 at 09:08 -0800, Eric Dumazet wrote:
> So we still have this huge contention on the reader-writer lock cache
> line...
> I would just remove it. (And remove hash rebuild, or make it RCU
> compatible )
I vote for removing the rebuild feature. It really doesn't make sense
to protect a 256Kb memory (using) hash, with very short lived elements,
against hash collision attacks, every 10 minutes. (Especially as we saw
a 7 GBit/s performance improvement)
Making the hash RCU "compatible" is not going to work, because the
elements are too short lived, thus we cannot free them fast enough
(call_rcu stuff). (I actually did the RCU implementation, to realize
this...)
next prev parent reply other threads:[~2012-11-30 12:56 UTC|newest]
Thread overview: 57+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-11-29 16:10 [net-next PATCH V2 0/9] net: fragmentation performance scalability on NUMA/SMP systems Jesper Dangaard Brouer
2012-11-29 16:11 ` [net-next PATCH V2 1/9] net: frag evictor, avoid killing warm frag queues Jesper Dangaard Brouer
2012-11-29 17:44 ` David Miller
2012-11-29 22:17 ` Jesper Dangaard Brouer
2012-11-29 23:01 ` Eric Dumazet
2012-11-30 10:04 ` Jesper Dangaard Brouer
2012-11-30 14:52 ` Eric Dumazet
2012-11-30 15:45 ` Jesper Dangaard Brouer
2012-11-30 16:37 ` Eric Dumazet
2012-11-30 21:37 ` Jesper Dangaard Brouer
2012-11-30 22:25 ` Eric Dumazet
2012-11-30 23:23 ` Jesper Dangaard Brouer
2012-11-30 23:47 ` Stephen Hemminger
2012-12-01 0:03 ` Eric Dumazet
2012-12-01 0:13 ` Stephen Hemminger
2012-11-30 23:58 ` Eric Dumazet
2012-12-04 13:30 ` [net-next PATCH V3-evictor] " Jesper Dangaard Brouer
2012-12-04 14:32 ` [net-next PATCH V3-evictor] net: frag evictor,avoid " David Laight
2012-12-04 14:47 ` [net-next PATCH V3-evictor] net: frag evictor, avoid " Eric Dumazet
2012-12-04 17:51 ` Jesper Dangaard Brouer
2012-12-05 9:24 ` Jesper Dangaard Brouer
2012-12-06 12:26 ` Jesper Dangaard Brouer
2012-12-06 12:32 ` Florian Westphal
2012-12-06 13:29 ` David Laight
2012-12-06 21:38 ` David Miller
2012-12-06 13:55 ` Jesper Dangaard Brouer
2012-12-06 14:47 ` Eric Dumazet
2012-12-06 15:23 ` Jesper Dangaard Brouer
2012-11-29 23:32 ` [net-next PATCH V2 1/9] " Eric Dumazet
2012-11-30 12:01 ` Jesper Dangaard Brouer
2012-11-30 14:57 ` Eric Dumazet
2012-11-29 16:11 ` [net-next PATCH V2 2/9] net: frag cache line adjust inet_frag_queue.net Jesper Dangaard Brouer
2012-11-29 16:12 ` [net-next PATCH V2 3/9] net: frag, move LRU list maintenance outside of rwlock Jesper Dangaard Brouer
2012-11-29 17:43 ` Eric Dumazet
2012-11-29 17:48 ` David Miller
2012-11-29 17:54 ` Eric Dumazet
2012-11-29 18:05 ` David Miller
2012-11-29 18:24 ` Eric Dumazet
2012-11-29 18:31 ` David Miller
2012-11-29 18:33 ` Eric Dumazet
2012-11-29 18:36 ` David Miller
2012-11-29 22:33 ` Jesper Dangaard Brouer
2012-11-29 16:12 ` [net-next PATCH V2 4/9] net: frag helper functions for mem limit tracking Jesper Dangaard Brouer
2012-11-29 16:13 ` [net-next PATCH V2 5/9] net: frag, per CPU resource, mem limit and LRU list accounting Jesper Dangaard Brouer
2012-11-29 17:06 ` Eric Dumazet
2012-11-29 17:31 ` David Miller
2012-12-03 14:02 ` Jesper Dangaard Brouer
2012-12-03 17:25 ` David Miller
2012-11-29 16:14 ` [net-next PATCH V2 6/9] net: frag, implement dynamic percpu alloc of frag_cpu_limit Jesper Dangaard Brouer
2012-11-29 16:15 ` [net-next PATCH V2 7/9] net: frag, move nqueues counter under LRU lock protection Jesper Dangaard Brouer
2012-11-29 16:15 ` [net-next PATCH V2 8/9] net: frag queue locking per hash bucket Jesper Dangaard Brouer
2012-11-29 17:08 ` Eric Dumazet
2012-11-30 12:55 ` Jesper Dangaard Brouer [this message]
2012-11-29 16:16 ` [net-next PATCH V2 9/9] net: increase frag queue hash size and cache-line Jesper Dangaard Brouer
2012-11-29 16:39 ` [net-next PATCH V2 9/9] net: increase frag queue hash size andcache-line David Laight
2012-11-29 16:55 ` [net-next PATCH V2 9/9] net: increase frag queue hash size and cache-line Eric Dumazet
2012-11-29 20:53 ` Jesper Dangaard Brouer
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