Snapshot with 250MiB new files to BackBlaze done in 1s? really?

Hi, I’m just wondering… is this right? I am snapshotting SQL logs - there’s a new 250MiB log every 15 minutes. I had the cron job on daily, now I put it on 15 minute intervals (5 minutes after the SQL backup itself), but it says it is complete in only 1s and 3s…
I mounted the snapshot and it looks like the file is there. How can this be?

Snapshotting root@pbs:/mnt/datastore/RAIDZ/samba ...
Created snapshot with root kbdac116bd6acca92b919165da9817ca4 and ID eb4da4fcadbf801cf6e292df541c578f in 1s

Snapshotting root@pbs:/mnt/datastore/RAIDZ/samba ...
Created snapshot with root ke716b7f510fec68c054d34ebb61c6c9f and ID 2928c5aebd9afe111075103240604b9b in 2s