Don't have a solution ... more info and a suggestion. I do see the time Wed. 23 Oct ... and today is 3 Nov - 11 days ago ... and did notice first column doesn't contain any info. .
Check php settings - time for a script to run, memory a script an consume (Server PHP info). If you can, increase those x2. Restart apache service.
I take it that your backup settings are set to default - include all users/all content, all logs? Might consider checking the length logs are kept ... set shorter.
Are you on shared hosting or dedicated?
How much memory does your server have?
Do have any old backups of the courses so you could get an idea of size of the backup?
Using file browser, check moodledata/temp/backup/ for hashnamed directories .. those are the directories that moodle creates to do backups/restores and copy of a course. Check the dates of those.
How quick were you to begin another backup/restore/copy process?
Moodle's cron job running the recommended once per minute?
'SoS', Ken