From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andi Kleen Subject: Re: Name hashing function causing a perf regression Date: Fri, 12 Sep 2014 12:11:06 -0700 Message-ID: <8761gs64dx.fsf@tassilo.jf.intel.com> References: <540F5562.1050505@fb.com> Mime-Version: 1.0 Content-Type: text/plain Cc: Linus Torvalds , , , , To: Josef Bacik Return-path: Received: from mga11.intel.com ([192.55.52.93]:22667 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751818AbaILTLI (ORCPT ); Fri, 12 Sep 2014 15:11:08 -0400 In-Reply-To: <540F5562.1050505@fb.com> (Josef Bacik's message of "Tue, 9 Sep 2014 15:30:42 -0400") Sender: linux-fsdevel-owner@vger.kernel.org List-ID: Josef Bacik writes: > > So the question is what do we do here? I tested other random strings > and every one of them ended up worse as far as collisions go with the > new function vs the old one. I assume we want to keep the word at a > time functionality, so should we switch to a different hashing scheme, > like murmur3/fnv/xxhash/crc32c/whatever? Or should we just go back to Would be interesting to try murmur3. -Andi -- ak@linux.intel.com -- Speaking for myself only