Hi,
I am currently recreating a remote backup from scratch, with the USB disk attached to a local Linux VM.
The backup speed however is very slow with an average speed of 5-6 MB/sec, and I can not relate this to any resource issue. It seems Duplicati is just “taking a break” for a minute in between every volume creation.
During this “break” top reports the VM is 99,2% idle, no I/O wait states, no memory limit, nothing. Neither does the VM host. dd throughput to the same local USB mountpoint is about 60 MB/sec.
I can get a little more speed by increasing the volume size from 100MB to 250MB, average 7-8MB/sec. I have also tried playing around with increasing the blocksize from default 100kb to 1MB, setting the Zip compression level to 1 (instead of default 9), enabling use-block-cache, but these settings don’t seem to make any real difference.
The backup source consists of ± 900 GB, ± 20.000 files. The Linux VM has access to 4 CPU cores, 2GB of memory. Running Duplicati version 2.0.6.3_beta_2021-06-17 on Debian 11.
Are these slow speeds to be expected, or might there be something wrong with my setup?