Pretty big incremental backups for idle computer

Backup agent for Microsoft Windows servers and workstations (formerly Veeam Endpoint Backup FREE)

Pretty big incremental backups for idle computer

Veeam Logoby mlabbe » Mon Oct 19, 2015 4:23 pm

Hi,

Am I the only one feeling the incremental backups create pretty big files even though it should have almost nothing to backup?

The initial backup size seems pretty normal (although I've seen better compression), but I'm trying VEB on a couple win7/8/10 test systems and they all create 1-2 GB (if not bigger) incremental backup files every day, even though these PCs have been sitting idle for several days.

hyberfile.sys and pagefile.sys are completely disabled on these systems (although I think VEB excludes these by default), and while I though "complete system" backups could include ram dump, I don't think "volume level backup" include ram state backup.

I also first thought it could be due to some background processes (e.g. windows update downloading big updates in the background, and these are backed up the next day), but then we wouldn't have a constant 1-2 GB incremental every day, on every OS.

I searched alot for infos on this but couldn't find explanations yet.
mlabbe
Influencer
 
Posts: 20
Liked: 4 times
Joined: Fri Oct 16, 2015 4:14 pm
Location: Quebec, Canada
Full Name: Michel Labbé

Re: Pretty big incremental backups for idle computer

Veeam Logoby PTide » Mon Oct 19, 2015 4:39 pm

Hi,

Any Windows OS has some background processes running when the machine is idle, some changes happen to system files during the process. The mount of blocks that are pulled into incremental depends on many factors such as filesystem block size, changed file's size and so on, however I doubt that this could be a cause for such a big backup. Another reason for large .vibs is a background defragmentation. When windows performs defrag it basically changes many blocks in order to get files' pieces together, thus many blocks on a harddrive get changed, while the data stays the same. Please try disabling disk defragmentation and see if anything changes.

Thank you.
PTide
Veeam Software
 
Posts: 3079
Liked: 252 times
Joined: Tue May 19, 2015 1:46 pm

Re: Pretty big incremental backups for idle computer

Veeam Logoby Dima P. » Mon Oct 19, 2015 5:36 pm

hyberfile.sys and pagefile.sys are completely disabled on these systems (although I think VEB excludes these by default)

Correct.

I doubt defrag can cause a serious backup file growth – all end-users windows operating systems have it enabled on a weekly basis by default. More likely the background process, for example, my OS’s incremental backup from an idle state varies from 0.7 – 3 Gigs.
Dima P.
Veeam Software
 
Posts: 6391
Liked: 449 times
Joined: Mon Feb 04, 2013 2:07 pm
Location: SPb
Full Name: Dmitry Popov

Re: Pretty big incremental backups for idle computer

Veeam Logoby mlabbe » Mon Oct 19, 2015 9:50 pm

PTide wrote:Please try disabling disk defragmentation and see if anything changes.


I confirm at least one of my test computers is running on SSD and have defrag completely disabled. Yet it still creates about 1GB (948 MB, 926 MB, etc) incrementals every day.

Dmitri said it's not unusual, but I still feel 1-2GB of block changes every day (out of 17GB of data for an idle desktop) is a bit huge. I wonder if it could be reduced by excluding a couple cache/temp dirs (I'll do so more testing on my own, I'm curious).

VEB is using block-mode backups (e.g. if a 100Kb email is added to a 10GB outlook.pst file, we expect that about 100kb is being added into the vib, not 10GB), right?

...unless (not how Outlook works but probably apply to other softwares) the software writes a separated 10GB+100Kb file and once the write is done, the original 10GB file is deleted, that would produce a 10GB (if not 20GB) incremental backup for a 100kb change in 1 file :| . Does that make sense?
mlabbe
Influencer
 
Posts: 20
Liked: 4 times
Joined: Fri Oct 16, 2015 4:14 pm
Location: Quebec, Canada
Full Name: Michel Labbé

Re: Pretty big incremental backups for idle computer

Veeam Logoby Dima P. » Thu Oct 22, 2015 9:28 pm

Yes, incremental backup is performed on a block level in VEB (volume level and entire PC backup – file level backup mode is another story). I suggest you to perform a backup of data volume only for the testing purposes and compare with OS volume. Data volume incremental should be tight.
Dima P.
Veeam Software
 
Posts: 6391
Liked: 449 times
Joined: Mon Feb 04, 2013 2:07 pm
Location: SPb
Full Name: Dmitry Popov


Return to Veeam Agent for Windows



Who is online

Users browsing this forum: No registered users and 8 guests