I've set up new server with ten 10Tb disks. Main volume is XFS over RAID6 (created with mdadm). For now fs is filling with data. After several hours of uptime disk IO freezes with such messages in log: [ 5679.900329] INFO: task tar:18235 blocked for more than 120 seconds. [ 5679.900404] Not tainted 4.18.12 #2 ... [ 5679.904044] INFO: task kworker/u24:3:18307 blocked for more than 120 seconds. [ 5679.904137] Not tainted 4.18.12 #2 Full log is too long, I left it here: https://bugzilla.kernel.org/show_bug.cgi?id=201331 I'm unsure, but it seems to be XFS-related. /proc/mdstat content: Personalities : [linear] [multipath] [raid0] [raid1] [raid6] [raid5] [raid4] [raid10] md0 : active raid1 sdf1[5] sda1[0] sdd1[3] sdg1[6] sdh1[7] sdi1[8] sdj1[9] sde1[4] sdb1[2] sdc1[1] 523712 blocks super 1.2 [10/10] [UUUUUUUUUU] md3 : active raid6 sda4[0] sdj4[9] sdg4[6] sdd4[3] sdi4[8] sdf4[5] sde4[4] sdh4[7] sdb4[2] sdc4[1] 77555695616 blocks super 1.2 level 6, 16384k chunk, algorithm 2 [10/10] [UUUUUUUUUU] bitmap: 9/73 pages [36KB], 65536KB chunk md2 : active raid10 sda3[0] sdh3[7] sdd3[3] sdj3[9] sdg3[6] sdf3[5] sdi3[8] sde3[4] sdb3[2] sdc3[1] 335216640 blocks super 1.2 512K chunks 2 near-copies [10/10] [UUUUUUUUUU] md1 : active (auto-read-only) raid10 sdj2[9] sdi2[8] sda2[0] sdf2[5] sdh2[7] sde2[4] sdg2[6] sdd2[3] sdb2[2] sdc2[1] 20951040 blocks super 1.2 512K chunks 2 near-copies [10/10] [UUUUUUUUUU] unused devices: <none> xfs_info output: meta-data=/dev/md3 isize=512 agcount=73, agsize=268431360 blks = sectsz=4096 attr=2, projid32bit=1 = crc=1 finobt=1 spinodes=0 rmapbt=0 = reflink=0 data = bsize=4096 blocks=19388923904, imaxpct=1 = sunit=4096 swidth=32768 blks naming =version 2 bsize=4096 ascii-ci=0 ftype=1 log =internal bsize=4096 blocks=521728, version=2 = sectsz=4096 sunit=1 blks, lazy-count=1 realtime =none extsz=4096 blocks=0, rtextents=0 I have made some RAID tuning: echo 32768 > /sys/block/md3/md/stripe_cache_size
