Btrfs send 4-5 times slower than rsync on local
Hello, i am using btrfs send to copy a snapshot to another btrfs filesystem on the same machine, and it has a maximum speed of 30-35MByte/sec. Incredibly rsync is much faster, at 120-140MB/sec. Source btrfs is a 5x2TB raid 0 and target is 1x4TB.
mount options: rw,noatime,compress-force=zlib,space_cache
kernel is linux-3.13.0-rc6-git and btrfs tools is built from git at about the same time linux-3.13.0-rc6 was released
Finally, is there a way to resume an interrupted send?
Quoted 5 lines · Konstantinos Skarlatos
Hello, i am using btrfs send to copy a snapshot to another btrfs filesystem on the same machine, and it has a maximum speed of 30-35MByte/sec. Incredibly rsync is much faster, at 120-140MB/sec. Source btrfs is a 5x2TB raid 0 and target is 1x4TB.
mount options: rw,noatime,compress-force=zlib,space_cache
kernel is linux-3.13.0-rc6-git and btrfs tools is built from git at about the same time linux-3.13.0-rc6 was released
I just sent a patch titled
[PATCH] Btrfs: only process as many file extents as there are refs
that should make this better. Also you are giving throughput but not actual times. How much time does it take to do a send vs an rsync. We may be sending less info across and therefore be done faster but at lower rates than rsync. Before this patch rsync won in my test case but only barely, and with this patch I'm 3 times faster than rsync even though I bet it's getting better throughput. Thanks,
Josef