From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from e23smtp09.au.ibm.com ([202.81.31.142]:36743 "EHLO e23smtp09.au.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753544AbaCRISO (ORCPT ); Tue, 18 Mar 2014 04:18:14 -0400 Received: from /spool/local by e23smtp09.au.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Tue, 18 Mar 2014 18:18:12 +1000 Received: from d23relay03.au.ibm.com (d23relay03.au.ibm.com [9.190.235.21]) by d23dlp03.au.ibm.com (Postfix) with ESMTP id 6850A3578054 for ; Tue, 18 Mar 2014 19:18:10 +1100 (EST) Received: from d23av03.au.ibm.com (d23av03.au.ibm.com [9.190.234.97]) by d23relay03.au.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id s2I8HuvX11469260 for ; Tue, 18 Mar 2014 19:17:56 +1100 Received: from d23av03.au.ibm.com (localhost [127.0.0.1]) by d23av03.au.ibm.com (8.14.4/8.14.4/NCO v10.0 AVout) with ESMTP id s2I8I9ZU016919 for ; Tue, 18 Mar 2014 19:18:09 +1100 From: chandan To: dsterba@suse.cz Cc: linux-btrfs@vger.kernel.org, aneesh.kumar@linux.vnet.ibm.com Subject: Re: [PATCH 0/6 EARLY RFC] Btrfs: Get rid of whole page I/O. Date: Tue, 18 Mar 2014 13:48 +0630 Message-ID: <1785327.CGV06aaKrn@localhost.localdomain> In-Reply-To: <20140317145555.GG29256@twin.jikos.cz> References: <1394634033-2528-1-git-send-email-chandan@linux.vnet.ibm.com> <20140317145555.GG29256@twin.jikos.cz> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Sender: linux-btrfs-owner@vger.kernel.org List-ID: Hello David, > I looked at previous postings of this patchset, but haven't found what > are the expected supported block sizes. > > I assume powers of two starting with 512b, until 64k. The earlier patchset posted by Chandra Seethraman was to get 4k blocksize to work with ppc64's 64k PAGE_SIZE. I chose to do 2k blocksize on x86_64's 4k PAGE_SIZE since that would allow others in the community to work/experiment with subpagesize-blocksize feature. The root node of "tree root" tree has 1957 bytes being written by make_btrfs() (in btrfs-progs). Hence I chose to do 2k blocksize for the initial subpagesize-blocksize work. So with this patchset the supported blocksizes would be in the range 2k-64k. Thanks, chandan