From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from plane.gmane.org ([80.91.229.3]:52176 "EHLO plane.gmane.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752428AbaEHPH4 (ORCPT ); Thu, 8 May 2014 11:07:56 -0400 Received: from list by plane.gmane.org with local (Exim 4.69) (envelope-from ) id 1WiPvN-0006Ky-Ta for linux-btrfs@vger.kernel.org; Thu, 08 May 2014 17:07:53 +0200 Received: from ip68-231-22-224.ph.ph.cox.net ([68.231.22.224]) by main.gmane.org with esmtp (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Thu, 08 May 2014 17:07:53 +0200 Received: from 1i5t5.duncan by ip68-231-22-224.ph.ph.cox.net with local (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Thu, 08 May 2014 17:07:53 +0200 To: linux-btrfs@vger.kernel.org From: Duncan <1i5t5.duncan@cox.net> Subject: Re: Balance performance problem with 3.14.1 Date: Thu, 8 May 2014 15:07:40 +0000 (UTC) Message-ID: References: <201405081950.23922.russell@coker.com.au> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-btrfs-owner@vger.kernel.org List-ID: Russell Coker posted on Thu, 08 May 2014 19:50:23 +1000 as excerpted: > I've got a server/workstation (KDE desktop and file server) running > kernel 3.14.1 from the Debian package 3.14-trunk-amd64. > > It was running well until I decided to do a full balance of the BTRFS > RAID-1 array of 3TB SATA disks (which hadn't been balanced before due to > previous kernels performing badly with scrub or balance). I canceled > the balance after about 5 days when it had been claiming to be about 65% > done for a day while doing a lot of disk IO. > > After canceling the balance the performance of the array has been poor. Not much help, but two comments: 1) I've seen other reports of performance problems after balance. Nobody seems to have a good reason as to why a balance might do that. 2) I've NOT seen anything like that, here. However, my btrfs are all rather small, under 50 GiB. (FWIW, it /still/ seems weird to me calling a GB "small". It doesn't seem all /that/ long ago that I bought my first 1 GB drive, and it sure wasn't small nor inexpensive then! I guess I've officially joined the computer old-timers!) -- Duncan - List replies preferred. No HTML msgs. "Every nonfree program has a lord, a master -- and if you use the program, he is your master." Richard Stallman