1. Single Disk 1.1 Creating the File System Wipe the disk 1 wipefs -a /dev/nvme0n1 Format the disk 1 mkfs.xfs /dev/nvme0n1 Mount the disk 1 2 mkdir -p /mnt/nvme0n1-test mount /dev/nvme0n1 /mnt/nvme0n1-test 1.2 Performance Test 4k random write 1 2 3 4 echo 3 > /proc/sys/vm/drop_caches fio --name=4k_randwrite --rw=randwrite --bs=4k --ioengine=libaio --direct=1 \ --numjobs=8 --iodepth=32 --size=20G --time_based --runtime=120 --group_reporting \ --allow_mounted_write=1 --filename=/mnt/nvme0n1-test/fio-4k-randwrite.

Btrfs supports online expansion, shrinking, disk replacement, and RAID mode conversion; this post covers creating a filesystem under RAID 0/RAID 1/RAID 10/RAID 6 topologies, adding disks, replacing disks, shrinking, and common operational tasks. 1. Btrfs Profiles single: single copy, no redundancy, works with one disk or can aggregate multiple disks.

1. Background and Prerequisites Compared with Ext4, Btrfs is a younger file system with more features to play with — snapshots, subvolumes, checksum self-verification, software RAID, and even transparent compression. That said, if you do not have the operations capability behind you, it is best not to use Btrfs. This article records the process of pulling a Btrfs disk out of a Synology DSM system and reading its data.