From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ravikiran G Thirumalai Subject: Re: [patch 9/11] net: dst_entry.refcount, use, lastuse to use alloc_percpu Date: Tue, 13 Sep 2005 15:07:37 -0700 Message-ID: <20050913220737.GA6249@localhost.localdomain> References: <20050913155112.GB3570@localhost.localdomain> <20050913161708.GK3570@localhost.localdomain> <20050913.132442.53540386.davem@davemloft.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: akpm@osdl.org, linux-kernel@vger.kernel.org, dipankar@in.ibm.com, bharata@in.ibm.com, shai@scalex86.org, rusty@rustcorp.com.au, netdev@vger.kernel.org Return-path: To: "David S. Miller" Content-Disposition: inline In-Reply-To: <20050913.132442.53540386.davem@davemloft.net> Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org On Tue, Sep 13, 2005 at 01:24:42PM -0700, David S. Miller wrote: > > There is no way in the world this enormous amount of NUMA > complexity is being added to the destination cache layer. Agreed the dst changes are ugly; that can be worked on. But the cacheline bouncing problem on the atomic_t dst_entry refcounter has been around for quite a while -- even on SMPs, not just NUMA. We need a solution for that. I thought you were against the dst_entry bloat caused by the previous version of the dst patch. alloc_percpu takes that away. You had concerns about workloads with low route locality. Unfortunately we don't have access to infrastructure setup for such tests :( As for the ugliness, would something on the lines of net_device refcounter patch in the series above be acceptable? Thanks, Kiran