From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from dkim1.fusionio.com ([66.114.96.53]:42952 "EHLO dkim1.fusionio.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756034Ab3GKPV2 convert rfc822-to-8bit (ORCPT ); Thu, 11 Jul 2013 11:21:28 -0400 Received: from mx1.fusionio.com (unknown [10.101.1.160]) by dkim1.fusionio.com (Postfix) with ESMTP id 52B817C0680 for ; Thu, 11 Jul 2013 09:21:28 -0600 (MDT) Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 To: , David Sterba , Mitch Harder From: Chris Mason In-Reply-To: <20130710225454.GJ25386@twin.jikos.cz> CC: Roger Pack , linux-btrfs References: <20130710225454.GJ25386@twin.jikos.cz> Message-ID: <20130711152126.12026.91759@localhost.localdomain> Subject: Re: lz4 status? Date: Thu, 11 Jul 2013 11:21:26 -0400 Sender: linux-btrfs-owner@vger.kernel.org List-ID: Quoting David Sterba (2013-07-10 18:54:54) > On Sun, Jun 30, 2013 at 12:35:09PM -0500, Mitch Harder wrote: > > There's been a parallel effort to incorporate a general set of lz4 > > patches in the kernel. > > > > I see these patches are currently queued up in the linux-next tree, so > > we may see them in the 3.11 kernel. > > The patches are now merged into 3.11. > > > It looks like lz4 and lz4hc will be provided. > > Regarding HC mode, there are some core compression code changes needed > in order to fully utilize the its potential, namely larger chunk size > that's compressed at a time. There was some tiny yet measurable gain of > HC against ordinary mode compared on current 4k-at-a-time > implementation, but the space savings did not justify the speed drop of > HC mode. > > I can't say if the patchset will be ready for 3.12 though. The current limits on the amount of data compressed at a time and the amount of delayed allocation sent down at a time were pulled out of the air. Changes to those limits are definitely ok if they are helping specific workloads. -chris