From: Stephane Chazelas Subject: Re: high CPU usage and low perf Date: Tue, 27 Sep 2011 10:31:58 +0100 Message-ID: <20110927093158.GB4149@yahoo.fr> References: <20110927091509.GA4149@yahoo.fr> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii To: linux-btrfs@vger.kernel.org Return-path: In-Reply-To: <20110927091509.GA4149@yahoo.fr> List-ID: 2011-09-27 10:15:09 +0100, Stephane Chazelas: [...] > a btrfs file system of mine started to behave very poorly with > some btrfs kernel tasks taking 100% of CPU time. > > # btrfs fi show /dev/sdb > Label: none uuid: b3ce8b16-970e-4ba8-b9d2-4c7de270d0f1 > Total devices 3 FS bytes used 4.25TB > devid 2 size 2.73TB used 1.52TB path /dev/sdc > devid 1 size 2.70TB used 1.49TB path /dev/sda4 > devid 3 size 2.73TB used 1.52TB path /dev/sdb > > Btrfs v0.19-100-g4964d65 > > FS mounted with compress-force,noatime > > (Can't do a "filesystem df" just now, as there's a umount > running, there should be around 33% free). [...] The umount just returned. # btrfs fi df /backup Data, RAID0: total=4.20TB, used=4.20TB Data: total=8.00MB, used=7.97MB System, RAID1: total=8.00MB, used=344.00KB System: total=4.00MB, used=0.00 Metadata, RAID1: total=162.75GB, used=59.30GB Metadata: total=8.00MB, used=0.00 It's now running fine again after reload of btrfs module and remount. -- Stephane