Backups too fast (600 MB/s)

[AlexLeadingEdge]

Hi guys,

I'm seeing really weird numbers in our backup times which have me worried...

7/05/2018 10:02:53 a.m. :: Hard disk 1 (127.0 GB) 24.0 GB read at 481 MB/s (sent in 55 seconds)
7/05/2018 10:03:57 a.m. :: Hard disk 2 (200.0 GB) 12.0 GB read at 600 MB/s (sent in 3 minutes and 19 seconds)
7/05/2018 10:09:22 a.m. :: Hard disk 1 (127.0 GB) 98.9 GB read at 542 MB/s ( sent in 3 minutes and 10 seconds)
7/05/2018 10:13:59 a.m. :: Hard disk 1 (50.0 GB) 38.1 GB read at 413 MB/s ( sent in 1 minute and 36 seconds)

This isn't physically possible for the drives to read this fast, and definitely not possible to send that much data (24 GB in 55 seconds) across a simple Ethernet network. Is this some sort of metadata speed calculation that includes things like compression and white space? What is the point of these kinds of statistics?

[foggy]

Is this an incremental job run?

[AlexLeadingEdge]

Yes.

[foggy]

Incremental runs are always significantly faster because they need to process only a few changed blocks, not the entire VMDK.

[AlexLeadingEdge]

So even though it says "98.9 GB read" it is only doing the changed blocks for that 98.9 GB? No wonder the speed calculation is absurd!

Perhaps Veeam B&R could start using actual data transferred divided by the time to give the actual speed?

[foggy]

This is not the transfer speed, but the speed of reading (processing) disk data. Transfer speed is calculated from the actually sent data.

[AlexLeadingEdge]

Ok, so just to recap...

98.9 GB read at 542 MB/s ( sent in 3 minutes and 10 seconds)

Am I correct in saying:
- B&R didn't actually read 98.9GB, it only read the changed blocks of that 98.9GB.
- B&R didn't actually read all 98.9GB at 542 MB/s, it read the changed blocks of that 98.9GB at 542MB/s.
- B&R didn't actually send 98.9 GB in 3 minutes and 10 seconds, it sent the changed blocks in 3 minutes and 10 seconds.

[foggy]

- B&R didn't actually read 98.9GB, it only read the changed blocks of that 98.9GB.

Correct.

- B&R didn't actually read all 98.9GB at 542 MB/s, it read the changed blocks of that 98.9GB at 542MB/s.

Not at 542MB/s, but at some actual speed. 542MB/s is calculated from the entire 98.9GB of "processed" disk data, most of which is simply skipped.

- B&R didn't actually send 98.9 GB in 3 minutes and 10 seconds, it sent the changed blocks in 3 minutes and 10 seconds.

Correct.

[RoyAyres]

I wish I had this problem!