From owner-freebsd-current@FreeBSD.ORG Thu Dec 17 09:27:34 2009 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 084C8106566C for ; Thu, 17 Dec 2009 09:27:34 +0000 (UTC) (envelope-from alexz@visp.ru) Received: from mail.visp.ru (srv1.visp.ru [91.215.204.2]) by mx1.freebsd.org (Postfix) with ESMTP id 8728B8FC0C for ; Thu, 17 Dec 2009 09:27:33 +0000 (UTC) Received: from 91-215-205-255.static.visp.ru ([91.215.205.255] helo=zagrebin) by mail.visp.ru with esmtp (Exim 4.66 (FreeBSD)) (envelope-from ) id 1NLCDf-000IFk-Hg for freebsd-current@freebsd.org; Thu, 17 Dec 2009 12:00:23 +0300 From: "Alexander Zagrebin" To: Date: Thu, 17 Dec 2009 12:00:23 +0300 Message-ID: <39309F560B98453EBB9AEA0F29D9D80E@vosz.local> MIME-Version: 1.0 Content-Type: text/plain; charset="koi8-r" Content-Transfer-Encoding: 7bit X-Mailer: Microsoft Office Outlook 11 Thread-Index: Acp+9135DWsMJaevS7ORggOUhWiWmQ== X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.5512 X-Mailman-Approved-At: Thu, 17 Dec 2009 12:33:00 +0000 Subject: 8.0-RELEASE: disk IO temporarily hangs up (ZFS or ATA related problem) X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 17 Dec 2009 09:27:34 -0000 Hi! I use onboard ICH7 SATA controller with two disks attached: atapci1: port 0x30c8-0x30cf,0x30ec-0x30ef,0x30c0-0x30c7,0x30e8-0x30eb,0x30a0-0x30af irq 19 at device 31.2 on pci0 atapci1: [ITHREAD] ata2: on atapci1 ata2: [ITHREAD] ata3: on atapci1 ata3: [ITHREAD] ad4: 1430799MB at ata2-master SATA150 ad6: 1430799MB at ata3-master SATA150 The disks are used for mirrored ZFS pool. I have noticed that the system periodically locks up on disk operations. After approx. 10 min of very slow disk i/o (several KB/s) the speed of disk operations restores to normal. gstat has shown that the problem is in ad6. For example, there is a filtered output of iostat -x 1: extended device statistics device r/s w/s kr/s kw/s wait svc_t %b ad6 818.6 0.0 10840.2 0.0 0 0.4 34 ad6 300.6 642.0 3518.5 24830.3 50 24.8 72 ad6 1.0 639.3 63.7 17118.3 0 62.1 98 ad6 404.5 4.0 6837.7 4.0 0 0.5 18 ad6 504.5 0.0 13667.2 0.0 1 0.7 32 ad6 633.3 0.0 13190.3 0.0 1 0.7 38 ad6 416.3 384.5 8134.7 24606.2 0 16.3 57 ad6 538.9 76.7 9772.8 2982.2 55 2.9 40 ad6 31.9 929.5 801.0 37498.6 0 27.2 82 ad6 635.5 0.0 13087.1 0.0 1 0.6 35 ad6 579.6 0.0 16669.8 0.0 0 0.8 43 ad6 603.6 0.0 11697.4 0.0 1 0.7 40 ad6 538.0 0.0 10438.7 0.0 0 0.9 47 ad6 30.9 898.4 868.6 40585.4 0 36.6 78 ad6 653.3 86.6 8566.6 202.7 1 0.8 40 ad6 737.1 0.0 6429.4 0.0 1 0.6 42 ad6 717.1 0.0 3958.7 0.0 0 0.5 36 ad6 1179.5 0.0 2058.9 0.0 0 0.1 15 ad6 1191.2 0.0 1079.6 0.0 1 0.1 15 ad6 985.1 0.0 5093.9 0.0 0 0.2 23 ad6 761.8 0.0 9801.3 0.0 1 0.4 31 ad6 698.7 0.0 9215.1 0.0 0 0.4 30 ad6 434.2 513.9 5903.1 13658.3 48 10.2 55 ad6 3.0 762.8 191.2 28732.3 0 57.6 99 ad6 10.0 4.0 163.9 4.0 1 1.6 2 Before this line we have a normal operations. Then the behaviour of ad6 changes (pay attention to high average access time and percent of "busy" significantly greater than 100): ad6 0.0 0.0 0.0 0.0 1 0.0 0 ad6 1.0 0.0 0.5 0.0 1 1798.3 179 ad6 1.0 0.0 1.5 0.0 1 1775.4 177 ad6 0.0 0.0 0.0 0.0 1 0.0 0 ad6 10.0 0.0 75.2 0.0 1 180.3 180 ad6 0.0 0.0 0.0 0.0 1 0.0 0 ad6 83.7 0.0 862.9 0.0 1 21.4 179 ad6 0.0 0.0 0.0 0.0 1 0.0 0 ad6 1.0 0.0 63.7 0.0 1 1707.4 170 ad6 1.0 0.0 9.0 0.0 0 1791.0 178 ad6 10.9 0.0 172.2 0.0 2 0.2 0 ad6 24.9 0.0 553.7 0.0 1 143.3 179 ad6 0.0 0.0 0.0 0.0 7 0.0 0 ad6 2.0 23.9 32.4 1529.9 1 336.3 177 ad6 0.0 0.0 0.0 0.0 1 0.0 0 ad6 68.7 0.0 1322.8 0.0 1 26.3 181 ad6 0.0 0.0 0.0 0.0 1 0.0 0 ad6 27.9 0.0 193.7 0.0 1 61.6 172 ad6 1.0 0.0 2.5 0.0 1 1777.4 177 ad6 0.0 0.0 0.0 0.0 1 0.0 0 ad6 1.0 0.0 2.0 0.0 1 1786.9 178 ad6 0.0 0.0 0.0 0.0 1 0.0 0 ad6 2.0 0.0 6.5 0.0 1 899.4 179 ad6 0.0 0.0 0.0 0.0 1 0.0 0 ad6 1.0 0.0 2.0 0.0 1 1786.7 178 ad6 0.0 0.0 0.0 0.0 1 0.0 0 And so on for about 10 minutes. Then the disk i/o is reverted to normal: ad6 139.4 0.0 8860.5 0.0 1 4.4 61 ad6 167.3 0.0 10528.7 0.0 1 3.3 55 ad6 60.8 411.5 3707.6 8574.8 1 19.6 87 ad6 163.4 0.0 10334.9 0.0 1 4.4 72 ad6 157.4 0.0 9770.7 0.0 1 5.0 78 ad6 108.5 0.0 6886.8 0.0 0 3.9 43 ad6 101.6 0.0 6381.4 0.0 0 2.6 27 ad6 109.6 0.0 7013.9 0.0 0 2.0 22 ad6 121.4 0.0 7769.7 0.0 0 2.4 29 ad6 92.5 0.0 5922.6 0.0 1 3.4 31 ad6 122.4 19.9 7833.0 1273.7 0 3.9 54 ad6 83.6 0.0 5349.5 0.0 0 3.9 33 ad6 5.0 0.0 318.4 0.0 0 8.1 4 There are no ata error messages neither in the system log, nor on the console. The manufacture's diagnostic test is passed on ad6 without any errors. The ad6 also contains swap partition. I have tried to run several (10..20) instances of dd, which read and write data from and to the swap partition simultaneously, but it has not called the lockup. So there is a probability that this problem is ZFS related. I have been forced to switch ad6 to the offline state... :( Any suggestions on this problem? -- Alexander Zagrebin