Our server has suddenly become extremely slow in writes. With % dd if=/dev/zero of=zero bs=2M count=2000 I get only 1.4MB/s in an almost idle machine. It has a raid6 with 6 disks, running 3.3.7. 3.4.2 doesn't improve matters. The important point is that it became so slow yesterday. No hardware has changed and all disks are fine. Reading from the filesystem is unaffected, at more than 85MB/s. The problem happens both in the root and home partitions. During the dd the disk utilization measured by sar is small: DEV tps rd_sec/s wr_sec/s avgrq-sz avgqu-sz await svctm %util sdb 93.30 254.40 931.20 12.71 0.57 6.10 4.16 38.77 sdc 100.50 244.00 970.40 12.08 0.76 7.59 3.80 38.20 sdd 101.40 261.60 927.20 11.72 0.68 6.68 3.74 37.90 sde 86.80 300.00 780.80 12.45 0.69 7.93 4.29 37.20 sdf 82.90 315.20 810.40 13.58 0.55 6.60 4.39 36.37 sda 96.70 220.00 984.00 12.45 0.47 4.87 3.72 35.94 So it seems that it's not a disk problem. Both filesystems reached 90% usage in space but less than 10% in inodes shortly before the slowness appeared. Now they're at 57% and 77% but still crawl. Could this be related? -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
