From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from userp2120.oracle.com ([156.151.31.85]:51822 "EHLO userp2120.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388112AbeLTRp7 (ORCPT ); Thu, 20 Dec 2018 12:45:59 -0500 Date: Thu, 20 Dec 2018 09:45:52 -0800 From: "Darrick J. Wong" Subject: Re: Same size drive has less usable space Message-ID: <20181220174552.GC27208@magnolia> References: <20181220131305.2a84b717@lud1.home> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20181220131305.2a84b717@lud1.home> Sender: linux-xfs-owner@vger.kernel.org List-ID: List-Id: xfs To: Luciano ES Cc: linux-xfs@vger.kernel.org On Thu, Dec 20, 2018 at 01:13:05PM -0200, Luciano ES wrote: > I have a new drive for backups. > I copied everything over and now I have this problem: > > Filesystem Size Used Avail Use% Mounted on > /dev/sda1 931G 914G 18G 99% /xx > /dev/sdb1 931G 920G 11G 99% /xxbkp > > So 914GB from the old drive expand and become 920GB. The new drive > is supposed to be the same size, but for some reason it can't > really hold it all. I will be forced to waste precious gigabytes. > > I tried to format the new one exactly like the old one, but > it was not possible: > > $ xfs_info /xx > meta-data=/dev/sda1 isize=256 agcount=8, agsize=30506944 blks > = sectsz=4096 attr=2, projid32bit=1 > = crc=0 finobt=0 spinodes=0 rmapbt=0 > = reflink=0 > data = bsize=4096 blocks=244055552, imaxpct=25 > = sunit=0 swidth=0 blks > naming =version 2 bsize=4096 ascii-ci=0 ftype=0 > log =internal bsize=4096 blocks=119167, version=2 > = sectsz=4096 sunit=1 blks, lazy-count=1 > realtime =none extsz=4096 blocks=0, rtextents=0 > > > $ xfs_info /xxbkp > meta-data=/dev/sdb1 isize=512 agcount=8, agsize=61013888 blks > = sectsz=512 attr=2, projid32bit=1 > = crc=1 finobt=1 spinodes=1 rmapbt=0 > = reflink=0 > data = bsize=2048 blocks=488111104, imaxpct=25 Just FYI you'll get a lot better performance from the filesystem if the blocksize is the same as cpu page size (4k I think) and if the filesystem isn't totally full. But yeah, either unmount /xx and use xfs_copy one disk to the other, or format the backup drive with the same parameters (I'll leave that to the other parts of this thread). --D > = sunit=0 swidth=0 blks > naming =version 2 bsize=4096 ascii-ci=0 ftype=1 > log =internal bsize=2048 blocks=238335, version=2 > = sectsz=512 sunit=0 blks, lazy-count=1 > realtime =none extsz=4096 blocks=0, rtextents=0 > > > I guess at least part of the problem is CRC enabled in the second > one. So, is there anything I can do to make all the data fit in the > new drive? > > TIA > > -- > Luciano ES > >>