From mboxrd@z Thu Jan 1 00:00:00 1970 From: Benjamin LaHaise Subject: regression: unregister_netdev() unusably slow Date: Sun, 24 May 2009 15:21:50 -0400 Message-ID: <20090524192150.GE24757@kvack.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii To: netdev@vger.kernel.org Return-path: Received: from kanga.kvack.org ([205.233.56.17]:43778 "EHLO kanga.kvack.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751335AbZEXTu6 (ORCPT ); Sun, 24 May 2009 15:50:58 -0400 Content-Disposition: inline Sender: netdev-owner@vger.kernel.org List-ID: Hi folks, I just ran a few L2TP tests against 2.6.30-rc7, and it looks like network device deletion has become unusably slow. At least in 2.6.27.10, deleting 1000 network interfaces takes less than 2 seconds of real time. The same test run under 2.6.30-rc7 is taking hundreds of seconds to delete 1000 interfaces at a rate of about 5 per second. The interfaces all share the same local ip address, but each have a single route to a unique client ip address. This is a fairly reasonable use-case, as a single L2TP daemon can be terminating thousands of client connections on a single tunnel, and a tunnel flap will require tearing down all these interfaces. I'll work on bisecting it, but if someone has any ideas of the source, I'd appreciate hearing about it. -ben