From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Ahern Subject: Re: [net PATCH] fib_trie: Drop unnecessary calls to leaf_pull_suffix Date: Mon, 27 Jul 2015 15:02:07 -0600 Message-ID: <55B69C4F.40506@cumulusnetworks.com> References: <55B6612C.7050506@cumulusnetworks.com> <20150727195631.26840.93266.stgit@ahduyck-vm-fedora22> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org To: Alexander Duyck , davem@davemloft.net Return-path: Received: from mail-ig0-f180.google.com ([209.85.213.180]:38639 "EHLO mail-ig0-f180.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753817AbbG0VCK (ORCPT ); Mon, 27 Jul 2015 17:02:10 -0400 Received: by iggf3 with SMTP id f3so94562106igg.1 for ; Mon, 27 Jul 2015 14:02:09 -0700 (PDT) In-Reply-To: <20150727195631.26840.93266.stgit@ahduyck-vm-fedora22> Sender: netdev-owner@vger.kernel.org List-ID: On 7/27/15 2:08 PM, Alexander Duyck wrote: > It was reported that update_suffix was taking a long time on systems where > a large number of leaves were attached to a single node. As it turns out > fib_table_flush was calling update_suffix for each leaf that didn't have all > of the aliases stripped from it. As a result, on this large node removing > one leaf would result in us calling update_suffix for every other leaf on > the node. > > The fix is to just remove the calls to leaf_pull_suffix since they are > redundant as we already have a call in resize that will go through and > update the suffix length for the node before we exit out of > fib_table_flush or fib_table_flush_external. > > Reported-by: David Ahern > Signed-off-by: Alexander Duyck > --- > > This patch should apply to linux-4.1.y and newer kernels. > > I've done a bit of testing on my system and I no longer see update_suffix > dominating the performance traces. David if you can test with this patch > to see if you still see the issue I would appreciate it. > Works for me. Thanks. Tested-by: David Ahern