Comment 25 for bug 1896578

Thanks Matt. I have it installed on one machine so far and looks good (in the past 10 minutes). fstrim of a ~30 TB RAID 10 took 73 seconds instead of multiple hours.

# uname -a
Linux xxx 5.4.0-75-generic #84-Ubuntu SMP Fri May 28 16:28:37 UTC 2021 x86_64 x86_64 x86_64 GNU/Linux
# df -h /dev/md0
Filesystem Size Used Avail Use% Mounted on
/dev/md0 30T 212G 29T 1% /opt/raid
# cat /proc/mdstat
Personalities : [raid10] [linear] [multipath] [raid0] [raid1] [raid6] [raid5] [raid4]
md0 : active raid10 nvme7n1[7] nvme2n1[2] nvme6n1[6] nvme4n1[4] nvme1n1[1] nvme3n1[3] nvme0n1[0] nvme5n1[5]
      31255576576 blocks super 1.2 512K chunks 2 near-copies [8/8] [UUUUUUUU]
      bitmap: 11/233 pages [44KB], 65536KB chunk

unused devices: <none>

# time fstrim /opt/raid

real 1m13.162s
user 0m0.004s
sys 0m0.351s