Missreported compression ratio

[Mikee]

Example: (same server, same Storage Group)

 

- 2/1/2004 3:24:54 AM: Copying First Storage Group on K3

2/1/2004 4:58:51 AM: Comparing First Storage Group on K3

2/1/2004 5:42:22 AM: Execution completed successfully

Completed: 3 files, 72.1 GB, with 66% compression

Performance: 1088.6 MB/minute (794.2 copy, 1730.9 compare)

Duration: 02:17:28 (00:01:57 idle/loading/preparing)

 

 

- 2/3/2004 3:31:18 AM: Copying First Storage Group on K3

2/3/2004 5:08:35 AM: Comparing First Storage Group on K3

2/3/2004 5:53:21 AM: Execution completed successfully

Completed: 3 files, 36.1 GB, with 33% compression

Performance: 527.4 MB/minute (384.2 copy, 840.5 compare)

Duration: 02:22:02 (00:02:06 idle/loading/preparing)

 

I assume it's just a reporting bug. Isn't it?

 

thanks,

 

Mikee

 

[natew]

Hi

 

Hard to say what it is at this point. I find it interesting that all of the data related stats (size, performance and compression) are roughly half as large on the bottom log entry. Its almost like the compression is proportionate to the data backed up?

 

Does it happen across other backups too?

 

Nate

 

 

[Mikee]

You're right, it seems like the size of the backup is being misreported (32.1 GB is the correct value) so that compression ratio doubles and in turn the speed doubles as well climing to impressive, but incorrect, >2000MB/minute sometimes

 

I usually don't pay attention to compression ratio. I trust that if (1) backup had no errors, (2) verification found nothing wrong- the backup was successful. Shouldn't that be the case?

 

 

 

thanks,

 

Mikee

[natew]

Hi

 

I agree, the reporting must be off somehow. I would trust that the backups are good.

Are the stats ever correct for this machine?

 

Nate

[Mikee]

The second log example is correct. I made a mistake in my previous post saying that the correct value is 32.1GB. I ment to type 36.1GB.

 

Mikee