Average data reduction

[vitalii.fesh]

Hi everyone,

I'm facing an issue with fetching data from a backup session, and I wanted to share an example to clarify the situation.

I have a test VM with an approximate size of 19GB ($job.Info.IncludedSize).

Initial full backup:
Backup size: 9GB ($session.backupstats.Backupsize)
Data size: 1.1TB ?? ($session.backupstats.DataSize)

First incremental backup:
Backup size: 700MB ($session.backupstats.Backupsize)
Data size: 5GB ($session.backupstats.DataSize)

Second incremental backup:
Backup size: 1MB
Data size: 1.1TB ??

I'm trying to calculate the average data reduction per job, but the numbers Veeam provides, especially the 1.1TB for data size, seem off. Is there an alternative way to fetch accurate data and calculate the reduction correctly?

Any suggestions would be greatly appreciated.

[david.domask]

Hi Vitalii,

Few questions quick:

1. Is this VM the only VM in the job or there are multiple VMs?
2. Are VMs added to the job individually as VMs or via some container? (Host, Folder, Resource Pool, Tag)

Can you show your code for this section and also the full output of $session.backupstats?

[vitalii.fesh]

Hi David,

1. Is this VM the only VM in the job or there are multiple VMs?
Only one VM

2. Are VMs added to the job individually as VMs or via some container? (Host, Folder, Resource Pool, Tag)
Individually using Create new job functionality in VBR console.


All sessions of this job:

Code: Select all

Get-VBRBackupSession | Where-Object {$_.Name -match "BJ-15" -and $_.Result -eq "Success"}
Job Name             State     Start Time            	 End Time              Result
--------             -----      ----------            	 --------             ------
BJ-15 (Full)          Stopped    8/8/2024 10:55:59 AM    8/8/2024 11:03:21 AM   Success
BJ-15 (Incremental)   Stopped    8/30/2024 12:52:46 PM   8/30/2024 1:13:35 PM   Success
BJ-15 (Incremental)   Stopped    9/9/2024 6:43:25 AM      9/9/2024 6:45:47 AM   Success

PS C:\Users\Administrator> $sessions.backupstats

BackupSize     	 DataSize 		DedupRatio 	CompressRatio
----------     	 -------- 		---------- 	-------------
9225481497 	1163936233006            0             79
 702223752    	   5154895253        	100            13
     30191         	95637        	100            31

[vitalii.fesh]

Hi David,

Do you think it's a bug or misconfiguration on my site?

[david.domask]

Hi Vitalii,

To be honest, it looks a little strange -- can I ask if you're in a position to remake the job and let it run once and see if the same results appear? We may need a Support case for this, but let's try this test if you're able first and see the results.

[vitalii.fesh]

Hi David,

I found a way to get what I wanted:
$session.Progress.ReadSize
$session.Progress.TransferedSize

I believe those values should help me to calculate the average data reduction per job.