Help with snapshots date

Hello all, I’m trying to better understand the output of restic snapshots in order to debug a problem.

I’m using a cronjob for a backup with OpenStack Swift as backend; this cronjob is scheduled to be run at 01:00 AM every night. This is the output of restic snapshots

ID               Date                            Host                       Tags          Directory
----------------------------------------------------------------------
6b86d799         2018-05-18 01:00:20             backup                     /data

And this is the output of restic backup command

scan [/data]
[0:06] 9359 directories, 82187 files, 76.497 GiB
scanned 9359 directories, 82187 files in 0:06
[13:02] 100.00%  76.497 GiB / 76.497 GiB  91546 / 91546 items  0 errors  ETA 0:00 

duration: 13:02
snapshot 6b86d799 saved

If I got it correctly, in this case duration: 13:02 should be the time requested to backup the data; if so, what does those 20 seconds in snapshots output mean?

Thanks in advance!

I have a suspicion: restic first loads and parses the index files from the repo, which may take some time, then it takes the current time and writes it to the timestamp. So when you start restic at 01:00 and it takes two seconds to lock the repo and load the index files, then you’ll end up with a timestamp for the new backup which is two seconds after 01:00.