Why can the speed be very slow when uploading files via supload(selectel)?

Question

Backup

Greetings.
Previously, backups were stored on one server and the speed of copying (ssh + mc) from others to it was quite high, but we thought about reliability and decided to use the cloud storage service, and it would be more than 10 times cheaper.
But the files are uploaded to the private container very slowly. 300mb (one file) loaded about 20 minutes. We have only one backup of the database in 9GB, and we have a lot of backups.
When copying, I turned off the checksum calculation, but this did not help much. At first, the TP said that they had just carried out the work. Nothing changed. They have 10Gb / s per storage host and it turns out the whole network is clogged?
Maybe I'm doing something wrong? Here is the command:
supload -u login -k pass -M -r backup_info/mysql/2015-01-24 /home/backup/mysql/2015-01-24
Or what do you recommend? I need something simple, according to the description everything fit, but the speed ...
UPD: I decided to pack everything into tar and upload it like that, not as convenient as I wanted, but at least something. The downside is that files larger than 5GB are not convenient to download, you have to split another archive.

Answer 1

We advise you to continue torturing technical support, these are their resources and only they know what and how they do.
Given the fact that their cloud and file storage is not popular, I think they can only dream of up to 10 gigabits. And even more so, I don’t think that they have 10 gigabits of file storage on the Internet.