Transfer via rclone mount much slower than rclone CLI (e.g. copy/sync)

[voorsboy]

I'm noticing that downloading files (read-only mount) by copying them from an rclone FUSE mount is significantly slower than downloading the same files from the same remote config to the same destination. I wasn't able to find any issues on Github regarding a speed discrepancy when downloading/copying files out of a mounted remote to a local filesystem.

For example, if I run something like:

rclone copy -P remote:/path/to/files /local/storage/

I will often max out my connection (~300 Mbit/s). If instead I try copying a file from the rclone mount:

rclone mount remote:/path/to/files /mnt/files --allow-other --umask 002

cp /mnt/files/some/file /home/files/file

I will only see transfer speeds of ~50 Mbit/s.

The config is a standard/default SFTP remote.

Version:

rclone v1.52.3
- os/arch: linux/amd64
- go version: go1.14.7

OS

Linux proxmox 5.4.44-2-pve #1 SMP PVE 5.4.44-2 (Wed, 01 Jul 2020 16:37:57 +0200) x86_64 GNU/Linux

fusermount version: 2.9.9

[Animosity022]

The debug logs would have helped to answer this one.

When you copy, it multi threads:

felix@lucidity:~$ rclone copy SFTP:/home/felix/test/jellyfish-400-mbps-4k-uhd-hevc-10bit.mkv . -vv
2020/08/24 20:18:54 DEBUG : rclone: Version "v1.52.3" starting with parameters ["rclone" "copy" "SFTP:/home/felix/test/jellyfish-400-mbps-4k-uhd-hevc-10bit.mkv" "." "-vv"]
2020/08/24 20:18:54 DEBUG : Using config file from "/opt/rclone/rclone.conf"
2020/08/24 20:18:54 DEBUG : sftp://felix@192.168.1.30:4022//home/felix/test/jellyfish-400-mbps-4k-uhd-hevc-10bit.mkv: New connection 192.168.1.95:61387->192.168.1.30:4022 to "SSH-2.0-OpenSSH_8.2p1 Ubuntu-4ubuntu0.1"
2020/08/24 20:18:55 DEBUG : fs cache: adding new entry for parent of "SFTP:/home/felix/test/jellyfish-400-mbps-4k-uhd-hevc-10bit.mkv", "SFTP:/home/felix/test"
2020/08/24 20:18:55 DEBUG : fs cache: renaming cache item "." to be canonical "/home/felix"
2020/08/24 20:18:55 DEBUG : jellyfish-400-mbps-4k-uhd-hevc-10bit.mkv: Need to transfer - File not found at Destination
2020/08/24 20:18:55 DEBUG : jellyfish-400-mbps-4k-uhd-hevc-10bit.mkv: Starting multi-thread copy with 4 parts of size 358.812M
2020/08/24 20:18:55 DEBUG : jellyfish-400-mbps-4k-uhd-hevc-10bit.mkv: multi-thread copy: stream 4/4 (1128726528-1504953150) size 358.798M starting
2020/08/24 20:18:55 DEBUG : jellyfish-400-mbps-4k-uhd-hevc-10bit.mkv: multi-thread copy: stream 3/4 (752484352-1128726528) size 358.812M starting
2020/08/24 20:18:55 DEBUG : jellyfish-400-mbps-4k-uhd-hevc-10bit.mkv: multi-thread copy: stream 2/4 (376242176-752484352) size 358.812M starting
2020/08/24 20:18:55 DEBUG : jellyfish-400-mbps-4k-uhd-hevc-10bit.mkv: multi-thread copy: stream 1/4 (0-376242176) size 358.812M starting
2020/08/24 20:18:55 DEBUG : sftp://felix@192.168.1.30:4022//home/felix/test/jellyfish-400-mbps-4k-uhd-hevc-10bit.mkv: New connection 192.168.1.95:61388->192.168.1.30:4022 to "SSH-2.0-OpenSSH_8.2p1 Ubuntu-4ubuntu0.1"
2020/08/24 20:18:55 DEBUG : sftp://felix@192.168.1.30:4022//home/felix/test/jellyfish-400-mbps-4k-uhd-hevc-10bit.mkv: New connection 192.168.1.95:61389->192.168.1.30:4022 to "SSH-2.0-OpenSSH_8.2p1 Ubuntu-4ubuntu0.1"

When you are using the mount, it does not.

That's the speed difference.