From mboxrd@z Thu Jan 1 00:00:00 1970 From: Florian Westphal Subject: Re: [PATCH nf-next] netfilter: xt_hashlimit: perform garbage collection from process context Date: Thu, 24 Jul 2014 10:27:44 +0200 Message-ID: <20140724082744.GA18404@breakpoint.cc> References: <1406176610.3363.29.camel@edumazet-glaptop2.roam.corp.google.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Pablo Neira Ayuso , Patrick McHardy , netfilter-devel@vger.kernel.org, netdev , Florian Westphal To: Eric Dumazet Return-path: Received: from Chamillionaire.breakpoint.cc ([80.244.247.6]:33934 "EHLO Chamillionaire.breakpoint.cc" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934120AbaGXI1t (ORCPT ); Thu, 24 Jul 2014 04:27:49 -0400 Content-Disposition: inline In-Reply-To: <1406176610.3363.29.camel@edumazet-glaptop2.roam.corp.google.com> Sender: netfilter-devel-owner@vger.kernel.org List-ID: Eric Dumazet wrote: > From: Eric Dumazet > > xt_hashlimit cannot be used with large hash tables, because garbage > collector is run from a timer. If table is really big, its possible > to hold cpu for more than 500 msec, which is unacceptable. > > Switch to a work queue, and use proper scheduling points to remove > latencies spikes. > > Later, we also could switch to a smoother garbage collection done > at lookup time, one bucket at a time... > > Signed-off-by: Eric Dumazet Reviewed-by: Florian Westphal Thanks Eric!