From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Laight Subject: RE: [v1 PATCH 1/14] rhashtable: Remove shift from bucket_table Date: Tue, 17 Mar 2015 11:22:44 +0000 Message-ID: <063D6719AE5E284EB5DD2968C1650D6D1CB02510@AcuExch.aculab.com> References: <20150315104306.GA21999@gondor.apana.org.au> <063D6719AE5E284EB5DD2968C1650D6D1CB024AB@AcuExch.aculab.com> <20150317105657.GE11089@casper.infradead.org> <20150317110041.GA11385@gondor.apana.org.au> Mime-Version: 1.0 Content-Type: text/plain; charset="Windows-1252" Content-Transfer-Encoding: 8BIT Cc: David Miller , "netdev@vger.kernel.org" , Eric Dumazet To: 'Herbert Xu' , "tgraf@suug.ch" Return-path: Received: from smtp-out6.electric.net ([192.162.217.181]:59841 "EHLO smtp-out6.electric.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932358AbbCQLYA convert rfc822-to-8bit (ORCPT ); Tue, 17 Mar 2015 07:24:00 -0400 In-Reply-To: <20150317110041.GA11385@gondor.apana.org.au> Content-Language: en-US Sender: netdev-owner@vger.kernel.org List-ID: From: Herbert Xu > Sent: 17 March 2015 11:01 > On Tue, Mar 17, 2015 at 10:56:57AM +0000, tgraf@suug.ch wrote: > > > > Given the discussions, the grow decision will likely change to > > a max bucket length limit anyway. > > Actually no. In my pathces the chain length is only used to > force an immediate rehash. Growing is still based on the number > of elements. > > The reason is that the maximum (not average) chain length actually > grows with the hash table size, even at 75% utilisation. That doesn't surprise me. But won't the rehashed table be just as likely to have a long list? So you are likely to get an immediate rehash? David