Debian 6 on HP proliant(2 cpu)with raid(2 * 1.5T RAID1 2 * 2T RAID1加入RAID0制作3.5T)主要运行nfs& imapd(加上用于
Windows共享的samba和用于预览网页的本地www);本地ubuntu桌面客户端安装$HOME,笔记本电脑访问imap&奇数文件(例如视频)通过nfs / smb;通过家用路由器/交换机连接100baseT或wifi的盒子
uname -a
Linux prole 2.6.32-5-686 #1 SMP Wed Jan 11 12:29:30 UTC 2012 i686 GNU/Linux
安装程序已经工作了几个月,但是很容易间歇性地进行非常缓慢的用户体验(从服务器或笔记本电脑播放视频的桌面安装$HOME)现在一直都很糟糕我不得不深入研究它以试图找出错误(！ )
服务器在低负载下似乎没问题(笔记本电脑)客户端(在本地磁盘上使用$HOME)连接到服务器的imapd和nfs挂载RAID以访问1个文件：top显示load~0.1或更少,0等待
但当(桌面)客户端安装$HOME并启动用户KDE会话(所有访问服务器)时,顶部显示例如
top - 13:41:17 up 3:43,3 users,load average: 9.29,9.55,8.27 Tasks: 158 total,1 running,157 sleeping,0 stopped,0 zombie cpu(s): 0.4%us,0.4%sy,0.0%ni,49.0%id,49.7%wa,0.0%hi,0.5%si,0.0%st Mem: 903856k total,851784k used,52072k free,171152k buffers Swap: 0k total,0k used,0k free,476896k cached PID USER PR NI VIRT RES SHR S %cpu %MEM TIME+ COMMAND 3935 root 20 0 2456 1088 784 R 2 0.1 0:00.02 top 1 root 20 0 2028 680 584 S 0 0.1 0:01.14 init 2 root 20 0 0 0 0 S 0 0.0 0:00.00 kthreadd 3 root RT 0 0 0 0 S 0 0.0 0:00.00 migration/0 4 root 20 0 0 0 0 S 0 0.0 0:00.12 ksoftirqd/0 5 root RT 0 0 0 0 S 0 0.0 0:00.00 watchdog/0 6 root RT 0 0 0 0 S 0 0.0 0:00.00 migration/1 7 root 20 0 0 0 0 S 0 0.0 0:00.16 ksoftirqd/1 8 root RT 0 0 0 0 S 0 0.0 0:00.00 watchdog/1 9 root 20 0 0 0 0 S 0 0.0 0:00.42 events/0 10 root 20 0 0 0 0 S 0 0.0 0:02.26 events/1 11 root 20 0 0 0 0 S 0 0.0 0:00.00 cpuset 12 root 20 0 0 0 0 S 0 0.0 0:00.00 khelper 13 root 20 0 0 0 0 S 0 0.0 0:00.00 netns 14 root 20 0 0 0 0 S 0 0.0 0:00.00 async/mgr 15 root 20 0 0 0 0 S 0 0.0 0:00.00 pm 16 root 20 0 0 0 0 S 0 0.0 0:00.02 sync_supers 17 root 20 0 0 0 0 S 0 0.0 0:00.02 bdi-default 18 root 20 0 0 0 0 S 0 0.0 0:00.00 kintegrityd/0 19 root 20 0 0 0 0 S 0 0.0 0:00.00 kintegrityd/1 20 root 20 0 0 0 0 S 0 0.0 0:00.02 kblockd/0 21 root 20 0 0 0 0 S 0 0.0 0:00.08 kblockd/1 22 root 20 0 0 0 0 S 0 0.0 0:00.00 kacpid 23 root 20 0 0 0 0 S 0 0.0 0:00.00 kacpi_notify 24 root 20 0 0 0 0 S 0 0.0 0:00.00 kacpi_hotplug 25 root 20 0 0 0 0 S 0 0.0 0:00.00 kseriod 28 root 20 0 0 0 0 S 0 0.0 0:04.19 kondemand/0 29 root 20 0 0 0 0 S 0 0.0 0:02.93 kondemand/1 30 root 20 0 0 0 0 S 0 0.0 0:00.00 khungtaskd 31 root 20 0 0 0 0 S 0 0.0 0:00.18 kswapd0 32 root 25 5 0 0 0 S 0 0.0 0:00.00 ksmd 33 root 20 0 0 0 0 S 0 0.0 0:00.00 aio/0 34 root 20 0 0 0 0 S 0 0.0 0:00.00 aio/1 35 root 20 0 0 0 0 S 0 0.0 0:00.00 crypto/0 36 root 20 0 0 0 0 S 0 0.0 0:00.00 crypto/1 203 root 20 0 0 0 0 S 0 0.0 0:00.00 ksuspend_usbd 204 root 20 0 0 0 0 S 0 0.0 0:00.00 khubd 205 root 20 0 0 0 0 S 0 0.0 0:00.00 ata/0 206 root 20 0 0 0 0 S 0 0.0 0:00.00 ata/1 207 root 20 0 0 0 0 S 0 0.0 0:00.14 ata_aux 208 root 20 0 0 0 0 S 0 0.0 0:00.01 scsi_eh_0
dmesg建议存在磁盘问题：
.............. (prevIoUs episode) [13276.966004] raid1:md0: read error corrected (8 sectors at 489900360 on sdc7) [13276.966043] raid1: sdb7: redirecting sector 489898312 to another mirror [13279.569186] ata4.00: exception Emask 0x0 SAct 0x1 SErr 0x0 action 0x0 [13279.569211] ata4.00: irq_stat 0x40000008 [13279.569230] ata4.00: Failed command: READ FPDMA QUEUED [13279.569257] ata4.00: cmd 60/08:00:00:6a:05/00:00:23:00:00/40 tag 0 ncq 4096 in [13279.569262] res 41/40:00:05:6a:05/00:00:23:00:00/40 Emask 0x409 (media error) <F> [13279.569306] ata4.00: status: { DRDY ERR } [13279.569321] ata4.00: error: { UNC } [13279.575362] ata4.00: configured for UDMA/133 [13279.575388] ata4: EH complete [13283.169224] ata4.00: exception Emask 0x0 SAct 0x1 SErr 0x0 action 0x0 [13283.169246] ata4.00: irq_stat 0x40000008 [13283.169263] ata4.00: Failed command: READ FPDMA QUEUED [13283.169289] ata4.00: cmd 60/08:00:00:6a:05/00:00:23:00:00/40 tag 0 ncq 4096 in [13283.169294] res 41/40:00:07:6a:05/00:00:23:00:00/40 Emask 0x409 (media error) <F> [13283.169331] ata4.00: status: { DRDY ERR } [13283.169345] ata4.00: error: { UNC } [13283.176071] ata4.00: configured for UDMA/133 [13283.176104] ata4: EH complete [13286.224814] ata4.00: exception Emask 0x0 SAct 0x1 SErr 0x0 action 0x0 [13286.224837] ata4.00: irq_stat 0x40000008 [13286.224853] ata4.00: Failed command: READ FPDMA QUEUED [13286.224879] ata4.00: cmd 60/08:00:00:6a:05/00:00:23:00:00/40 tag 0 ncq 4096 in [13286.224884] res 41/40:00:06:6a:05/00:00:23:00:00/40 Emask 0x409 (media error) <F> [13286.224922] ata4.00: status: { DRDY ERR } [13286.224935] ata4.00: error: { UNC } [13286.231277] ata4.00: configured for UDMA/133 [13286.231303] ata4: EH complete [13288.802623] ata4.00: exception Emask 0x0 SAct 0x1 SErr 0x0 action 0x0 [13288.802646] ata4.00: irq_stat 0x40000008 [13288.802662] ata4.00: Failed command: READ FPDMA QUEUED [13288.802688] ata4.00: cmd 60/08:00:00:6a:05/00:00:23:00:00/40 tag 0 ncq 4096 in [13288.802693] res 41/40:00:05:6a:05/00:00:23:00:00/40 Emask 0x409 (media error) <F> [13288.802731] ata4.00: status: { DRDY ERR } [13288.802745] ata4.00: error: { UNC } [13288.808901] ata4.00: configured for UDMA/133 [13288.808927] ata4: EH complete [13291.380430] ata4.00: exception Emask 0x0 SAct 0x1 SErr 0x0 action 0x0 [13291.380453] ata4.00: irq_stat 0x40000008 [13291.380470] ata4.00: Failed command: READ FPDMA QUEUED [13291.380496] ata4.00: cmd 60/08:00:00:6a:05/00:00:23:00:00/40 tag 0 ncq 4096 in [13291.380501] res 41/40:00:05:6a:05/00:00:23:00:00/40 Emask 0x409 (media error) <F> [13291.380577] ata4.00: status: { DRDY ERR } [13291.380594] ata4.00: error: { UNC } [13291.386517] ata4.00: configured for UDMA/133 [13291.386543] ata4: EH complete [13294.347147] ata4.00: exception Emask 0x0 SAct 0x1 SErr 0x0 action 0x0 [13294.347169] ata4.00: irq_stat 0x40000008 [13294.347186] ata4.00: Failed command: READ FPDMA QUEUED [13294.347211] ata4.00: cmd 60/08:00:00:6a:05/00:00:23:00:00/40 tag 0 ncq 4096 in [13294.347217] res 41/40:00:06:6a:05/00:00:23:00:00/40 Emask 0x409 (media error) <F> [13294.347254] ata4.00: status: { DRDY ERR } [13294.347268] ata4.00: error: { UNC } [13294.353556] ata4.00: configured for UDMA/133 [13294.353583] sd 3:0:0:0: [sdc] Unhandled sense code [13294.353590] sd 3:0:0:0: [sdc] Result: hostbyte=DID_OK driverbyte=DRIVER_SENSE [13294.353599] sd 3:0:0:0: [sdc] Sense Key : Medium Error [current] [descriptor] [13294.353610] Descriptor sense data with sense descriptors (in hex): [13294.353616] 72 03 11 04 00 00 00 0c 00 0a 80 00 00 00 00 00 [13294.353635] 23 05 6a 06 [13294.353644] sd 3:0:0:0: [sdc] Add. Sense: Unrecovered read error - auto reallocate Failed [13294.353657] sd 3:0:0:0: [sdc] CDB: Read(10): 28 00 23 05 6a 00 00 00 08 00 [13294.353675] end_request: I/O error,dev sdc,sector 587557382 [13294.353726] ata4: EH complete [13294.366953] raid1:md0: read error corrected (8 sectors at 489900544 on sdc7) [13294.366992] raid1: sdc7: redirecting sector 489898496 to another mirror
而且它们经常发生,我想这可能会导致性能问题(？)
#dmesg | grep镜子
[12433.561822] raid1: sdc7: redirecting sector 489900464 to another mirror [12449.428933] raid1: sdb7: redirecting sector 489900504 to another mirror [12464.807016] raid1: sdb7: redirecting sector 489900512 to another mirror [12480.196222] raid1: sdb7: redirecting sector 489900520 to another mirror [12495.585413] raid1: sdb7: redirecting sector 489900528 to another mirror [12510.974424] raid1: sdb7: redirecting sector 489900536 to another mirror [12526.374933] raid1: sdb7: redirecting sector 489900544 to another mirror [12542.619938] raid1: sdc7: redirecting sector 489900608 to another mirror [12559.431328] raid1: sdc7: redirecting sector 489900616 to another mirror [12576.553866] raid1: sdc7: redirecting sector 489900624 to another mirror [12592.065265] raid1: sdc7: redirecting sector 489900632 to another mirror [12607.621121] raid1: sdc7: redirecting sector 489900640 to another mirror [12623.165856] raid1: sdc7: redirecting sector 489900648 to another mirror [12638.699474] raid1: sdc7: redirecting sector 489900656 to another mirror [12655.610881] raid1: sdc7: redirecting sector 489900664 to another mirror [12672.255617] raid1: sdc7: redirecting sector 489900672 to another mirror [12672.288746] raid1: sdc7: redirecting sector 489900680 to another mirror [12672.332376] raid1: sdc7: redirecting sector 489900688 to another mirror [12672.362935] raid1: sdc7: redirecting sector 489900696 to another mirror [12674.201177] raid1: sdc7: redirecting sector 489900704 to another mirror [12698.045050] raid1: sdc7: redirecting sector 489900712 to another mirror [12698.089309] raid1: sdc7: redirecting sector 489900720 to another mirror [12698.111999] raid1: sdc7: redirecting sector 489900728 to another mirror [12698.134006] raid1: sdc7: redirecting sector 489900736 to another mirror [12719.034376] raid1: sdc7: redirecting sector 489900744 to another mirror [12734.545775] raid1: sdc7: redirecting sector 489900752 to another mirror [12734.590014] raid1: sdc7: redirecting sector 489900760 to another mirror [12734.624050] raid1: sdc7: redirecting sector 489900768 to another mirror [12734.647308] raid1: sdc7: redirecting sector 489900776 to another mirror [12734.664657] raid1: sdc7: redirecting sector 489900784 to another mirror [12734.710642] raid1: sdc7: redirecting sector 489900792 to another mirror [12734.721919] raid1: sdc7: redirecting sector 489900800 to another mirror [12734.744732] raid1: sdc7: redirecting sector 489900808 to another mirror [12734.779330] raid1: sdc7: redirecting sector 489900816 to another mirror [12782.604564] raid1: sdb7: redirecting sector 1242934216 to another mirror [12798.264153] raid1: sdc7: redirecting sector 1242935080 to another mirror [13245.832193] raid1: sdb7: redirecting sector 489898296 to another mirror [13261.376929] raid1: sdb7: redirecting sector 489898304 to another mirror [13276.966043] raid1: sdb7: redirecting sector 489898312 to another mirror [13294.366992] raid1: sdc7: redirecting sector 489898496 to another mirror
尽管阵列仍在所有磁盘上运行 – 但它们还没有放弃：
#cat / proc / mdstat
Personalities : [raid1] [raid0]
md10 : active raid0 md0[0] md1[1]
3368770048 blocks super 1.2 512k chunks
md1 : active raid1 sde2[2] sdd2[1]
1464087824 blocks super 1.2 [2/2] [UU]
md0 : active raid1 sdb7[0] sdc7[2]
1904684920 blocks super 1.2 [2/2] [UU]
unused devices: <none>
所以我想我已经知道问题是什么,但我不是想象力最远的一个linux系统管理员专家,我真的很感激这里的线索检查我的诊断和我需要做什么：
>显然我需要为sdc采购另一个驱动器. (我猜我
如果价格合适,可以购买更大的驱动器：我在想
有一天,我需要增加数组的大小,那将是
一个较少的驱动器更换一个更大的驱动器)
>然后使用mdadm来失败现有的sdc,删除它并适合新的驱动器
> fdisk新驱动器与阵列的分区大小相同
>使用mdadm将新驱动器添加到阵列中
听起来不错？
解决方法
通常当您遇到磁盘错误时,磁盘会暂停一段时间以尝试纠正错误本身,并且Linux RAID将容忍某些磁盘等待,直到它标记为坏.这个磁盘暂停可能是导致速度减慢的原因(特别是在您看到的错误率时).
您更换驱动器的计划是正确的.但是,我不建议使用更换RAID的分区部分的概念来获得更大的驱动程序,然后再部分使用其他东西.更接近原始磁盘(大小和速度)以保持阵列一致更为明智.也就是说,从理论上讲,你可以做得更大,并为数组替换分配确切的替换大小,然后为其他东西(甚至是数组的另一个成员)划分另一个分区.
可能有助于调试的旁注：我喜欢用作顶部替换的工具称为atop(http://www.atoptool.nl/),它可以让您更加可视化使用磁盘I / O的每个磁盘和进程以及瓶颈所在的位置(您可能会注意到等待I / O是针对具有问题的特定磁盘).
