I setup a Backblaze B2 bucket, and the first full backup was 110GB (per the B2 console). That backup job only took 20 minutes, at an average rate of 94MB/s (BYTES). My internet connection is 1Gbps symmetrical, so it saturated my bandwidth (which is awesome). However, I immediately ran a verification job for the B2 bucket, and that took 2 hours and 24 minutes. Is it expected that a verification job is 7x slower than a backup job?
PBS 4.0 Backblaze B2 Verification Performance Issue?
- Thread starter TrustyHippo
- Start date
I do NOT use Backblaze, so take my idea with a grain of salt:
When you write a new backup the data is transferred to Backblaze. I am pretty sure they have fast (and secure) storage to put that incoming data in, before it is transferred to the final destination in their large, multi-tiered warehouse - minutes, hours or days later. Because of the pure amount of data they store that may very well be on rotating spindles.
You, the customers, see only the fast speed.
When you verify an "old" backup each and every chunk (below 4MB in size) has to be read individually (as those read-commands are one-after-another, not in a single large request) from the location, where it is actually stored. If that is rotating rust it gets slow quickly.
Again: pure guessing...
