From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [net-next PATCH V2 3/9] net: frag, move LRU list maintenance outside of rwlock Date: Thu, 29 Nov 2012 13:31:08 -0500 (EST) Message-ID: <20121129.133108.427624036846294750.davem@davemloft.net> References: <1354211659.3299.15.camel@edumazet-glaptop> <20121129.130506.329791401604974668.davem@davemloft.net> <1354213492.3299.22.camel@edumazet-glaptop> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: brouer@redhat.com, fw@strlen.de, netdev@vger.kernel.org, pablo@netfilter.org, tgraf@suug.ch, amwang@redhat.com, kaber@trash.net, paulmck@linux.vnet.ibm.com, herbert@gondor.hengli.com.au To: eric.dumazet@gmail.com Return-path: Received: from shards.monkeyblade.net ([149.20.54.216]:34159 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754259Ab2K2SbL (ORCPT ); Thu, 29 Nov 2012 13:31:11 -0500 In-Reply-To: <1354213492.3299.22.camel@edumazet-glaptop> Sender: netdev-owner@vger.kernel.org List-ID: From: Eric Dumazet Date: Thu, 29 Nov 2012 10:24:52 -0800 > On Thu, 2012-11-29 at 13:05 -0500, David Miller wrote: > >> Replace 1024 in your formula with X and the limit is therefore >> controlled by X. >> >> So it seems the high_thresh can be replaced with an appropriate >> determination of X to size the hash. >> >> If X is 256, that limits us to ~130MB per cpu. >> > > per host, as the table would be shared by all cpus. I think a per-cpu hash might make more sense. This would scale our limits to the size of the system. I'm willing to be convinced otherwise, but it seems the most sensible thing to do.