Has Vista rendered Incrementals obsolete?

My experience with incremental backups is that on the whole they are now the same or almost the same size as "full backups" with Vista. Take my own case as an example - I have a full image backup with the scheduler set to do weekly incrementals thereafter. The full backup file is 61.4 gig and the incremental has just completed and that is 60.9 gig. As far as I can see the reason for this is that Vista performs low level defragging also once a week hence the files are constantly being rearranged hence Acronis having to make an almost total new build every week.

One would have thought that Acronis might have realised this by now given that Vista has been on general release for almost 2 years.

 

Faust:

I don't do incremental backups as a general rule, but recently did a few while rebuilding the user profile on my Vista machine. Here's what I found:

Full backup of Vista partition - 12 GB
Incremental one day later - 0.49 GB
Incremental one week later - 1.4 GB

I was making quite a few changes in the interim (adding/removing programs, customizing, etc), but in general I think most of the growth came from the daily restore points/shadow copies, which grew from 1 GB to 3 GB during the above time period.

Also, I have the auto defrag task disabled in Vista, preferring instead to do manual defrags with PerfectDisk. No defragmentation took place during the above time period. Perhaps you could test this by turning off defragmentation and repeating your weekly incremental to see what happens.

 

Hi k0lo,

I know without doubt that it is indeed the auto defrag feature in Vista that causes this issue with incrementals. Really the point I am making is that if the average PC user or perhaps Joe Public for want of a better word follows the default options in Vista and then installs a programme like Acronis, what then is the real value of the incremental backup and just how long a time will it take come consolidation time and how much HD space will they take up. Again take my example of one simple volume 60 gig - 1 full backup plus 3 incrementals over the month, that's a file size of some 240 gig with auto defrag enabled. I can see the average user coming to grief very quickly if they don't understand what is going on. I am surprised that Acronis don't mention this could be an issue in the install instructions especially in the latest version which seems to be aimed more at Vista users.

 

Faust:

Auto defrag sounds like a highly plausible suspect, but you won't know for sure until you do an experiment. Are you certain that auto defrag is the only cause of this behavior??

 

Yes, if I disable defrag or an incremental is done prior to defrag having run then the file size is around 4 gig, do one after defrag has run and the incremental is almost the same size as the main. This must be because defrag puts files back into different areas on the disk so an incremental has almost to start from a blank canvass again.

 

Am surprised that there is that much rearranging being done by a defrag. For curiosity, what is the output from the following command when run from an elevated command prompt?

Code:

vssadmin list shadowstorage

 

From page 18 of the 2009 manual:
"An incremental or differential backup created after a disk is defragmented might be considerably larger than usual. This is because the defragmentation program changes file locations on disk and the backups reflect these changes. Therefore, it is recommended that you re-create a full backup after disk defragmentation."

 

I've noticed the same thing as Faust. Incrementals in Vista are usually as large as the Full if they are a week or more later than the Full. Sometimes it doesn't even take a week (it probably depends on the defrag schedule). I have left the Vista defrag as default and I have System Restore turned off.

As a result, I mainly do Full backups. On occasion, I do an Incremental (before installing a program, for example). However, since I do Validations, it wastes time to create an Incremental the same size as the Full and then wait twice as long for the Validation to finish because it needs to check them both. For my backup schedule, there are no savings of either space or time by doing Incrementals on the Vista partition.

I do create Incremental images of my data partitions. The defrag doesn't seem to affect them nearly as much. Months can pass and the size stays normal.

---

Mark,

Since you use a different defrag program, do you notice that it moves everything around every time it defrags? It seems that the Vista program must do this.

 

Well this may not be totally scientific but I have just completed the same experiment tonight using AusLogics defrag program and guess what - yep another incremental as large as the full backup.

I mused over the quote from the 2009 instruction manual MudCrab - whilst Acronis warn the user about this they don't seem to have taken into account that Vista defrag is turned on by default. Anyone buying TI 2009 is in for a surprise using the task scheduler as it only lets you do one full backup followed by incrementals. There may be nothing that any of these backup software providers can do about this issue. However, Vista certainly does them no favours in relation to this matter.

 

I think that my method has two things going for it:

1. PerfectDisk does not move files that don't change unless it is consolidating free space. The program's algorithm classifies files into four groups and orders them on the disk in this sequence; boot files, files that are rarely modified (not in the last 60 days), files that are occasionally modified (not in the last 30 days), and files that have been recently modified. Thus, most of the files on the disk that change are in one general location and they are the ones that get defragmented.

2. With Vista, VSS (Volume Shadow Copy Service) runs daily and keeps track of sectors that have changed. When you defragment a disk you not only move the location of the sectors on the disk, but also the Shadow Copy storage area grows because it is keeping track of each relocation. To minimize this growth, I've changed the default cluster size on my disk from 4k to 16k. This is something Microsoft recommends for their server operating systems where VSS is running, but it also applies to Vista and Server 2008. Using 16 k clusters seems to have made a difference; in my case I now get 4 times as many Shadow Copies (Previous Versions of Files) in the same amount of disk space, so you can infer that fewer sectors must be moving around during defragmentation runs.

I have a hunch that #2 is the main reason for the growth in True Image incremental backups, in my opinion, and that is why I asked Faust for some of his VSS details. It might be helpful to know the size of his disk, the used space on the disk, and the amount of space used by VSS. Maybe we can estimate the amount of change taking place on his system in a week and compare to the size of his incremental backup to see if it all makes sense.

Finally, getting back to the original question, yes; defragmenting with PerfectDisk has worked out better for me than using the Vista defragmenter. After using PD for a couple of years I've modified my defrag habits from once weekly to once monthly, which now seems perfectly adequate.

 

Hi again K0lo

The HD is a 500 gig WD Blue - well actually it's 458 gig with 368 gig free space one simple volume.

I don't think looking at my PC usage that defrag needs to run anywhere near as often as the Vista weekly defrag. With this in mind I have disabled auto defrag and set myself a calender reminder to defrag the drive once a month. I may just use the AusLogics defrag programme as it's far quicker than Vista in any event. Acronis is due to run an incremental today and as there has been no defrag since the full backup yesterday I will be interested to see the results later on.

 

Right this surely cannot be correct - this is the result for the incremental backup completed today at 11.22 am

Full backup file created yesterday 66,612,516

Incremental created today 66,641,651

Apart from some Internet surfing the only other activity has been a couple of emails two word documents and the nightly backup that the Maxtor software performs for any changes to data and backups up to external HD.

I am currently using TI 11 - no defrag has taken place or is enabled.

 

Faust:

Was this a manual incremental image that you initiated yourself, or was it initiated by the TI scheduler?

Try a chkdsk /f on your disk -- perhaps TI has reverted to backing up in sector-by-sector mode, which it will do if it detects any problems with the partition. Although if that's the case wouldn't it back up all 485 GB worth of sectors?

If you have system restore enabled on your disk the amount of space reserved for shadow copies will be 15% of the drive by default, or about 68.7 GiB. How much of that is in use by VSS currently (vssadmin list shadowstorage)?

Finally, does the Maxtor backup software set/reset the archive bit on each file as it backs up? Could this account for TI's interpretation of changed sectors?

 

chdsk reveals good clean state - don't know how the Maxtor works but as it isn't due to start until 20:00 hours tonight I am about to repeat the experiment. The backups are scheduled by the way.

Used Shadow Storage Space 8.446
Allocated 10.439
Maximum 68.738

This was incremental and sector by sector is not ticked and as you say would be far larger.

Maxtor only backs up any changes to personal data that have taken place since backup e.g. new word docs. If no changes then backup takes less than 10 secs. The only changes were the two word docs.

 

Faust:

Very curious. You do not have an inordinate amount of space used by VSS, the file system checks out OK, and if the Maxtor backup only takes 10 sec then it can't be flipping too many archive bits. So what is it??

Several people on the forum have reported that TI only does full backups for them even though they have scheduled an incremental backup. It is beginning to sound like this is also happening to you.

If you wait a day after having no defragmentation, no major changes, and only the daily system restore point and then you do a manual incremental backup image, how large is it?

 

I think I may have got to the bottom of this mystery. My main backups were done manually through the backup and restore icon in the GUI. However, for the incrementals I have then used the scheduler. Even though the scheduler must have located that there is a backup in "backup locations" as incremental is pre-selected when the task is set up, it appears that it is not being linked with the main as the incremental is the same file size as the full backup. I have just finished doing two fulls and two incrementals (to slave and external HD) through the scheduler and this time the incrementals are less than 2 gig.

It is a mystery though why scheduler cannot see the full backups as such then attach subsequent small incrementals.

 

Don't worry there are plenty more obscure " features" of TI 21009 to come. Enough to keep you bemused for days on end.

Xpilot

 

This is the infamous TI 11. I downloaded the trial version of 2009 the other night and it worked flawlesly, by far the most reliable version yet on my newest PC. Very quick backups and the restores were just as quick, no more seventeen hour restores and that was without the need for a VistaPE disk. Restores measured in minutes for 60 gig and successful. The only thing that put me off was the backup regime - no facility to do multiple full backups from scheduler.

For the most part TI 11 now appears to be behaving itself as well, even this version will do a restore within the hour without the VistaPE disk. I think I have got to the bottom of the incremental issue as I said in my last post but have no idea why TI is behaving in this way.

 

I just disabled auto defrag, but when I next opened the Disk Defragmenter, the stupid program started a defrag.

How do I totally disable disk defragmentation?

I have Perfect Disk, but not yet installed.

 

Howard:

You can type "defrag" in the Start/Search box and choose "Disk Defragmenter". Doing this will bring up the following dialog box:



Un-check the box "Run on a schedule". When you open Disk Defragmenter an analysis will start, but if you had disabled the defragmenter it will only analyze the disk and report the results; it won't defragment.

By the way, I forgot to defragment last month so what you see is an analysis of a Vista disk that was last defragmented 2 months ago. As I said in a previous post, PerfectDisk does a pretty decent job of arranging files so that fragmentation is kept to a minimum going forward. And it works pretty darned well.

 

More times than I can remember I have heard this about Vista and defragging and incremental backups. But, on two different machines, using V11 on each, and Vista Home Basic on the desktop and Vista Home Premium SP1 on the laptop, I do not experience this problem. My machines both are scheduled to defrag every week, and do seem to stay fairly well defragged. But my main backups are about 50 Gigs, and the incrementals, two each week, are around 1.3 - 5 Gigs. I am making a full backup twice each week, and adding two incrementals to it, so that there are six recovery images each week on each machine.

I have never seen the large incremental in the almost two years I have been using Vista with Version 11.

I don't know what the explanation is, but I think you might be well advised to look elsewhere than Vista.

Good luck, whatever you do.

 

Wandering2:

The OP (Faust) found his problem, and it wasn't Vista. It was the way that he had set TI up to do incremental backups (see post #16). In reality TI was doing full backups.

 

As you say problem solved, though I still cannot fathom why task scheduler still makes the incremental as a new full backup after self selecting incremental in the task setup wizard. Task knows a full backup exists then simply ignores it.

 

I don't have access to the TI 11 User's Guide, but the following quote is from the TI 10 User's Guide:

So it appears that you have to let the scheduler create the first backup as a full. Subsequent backups should be incremental. Again, this is from version 10 and the behavior in version 11 may be different.

 

Yes, I found that dialog.

View attachment 203619

Yes, I saw that.
It's very bad design to not separate setting the options from the analysis.
I have no interest in Vista's analysis.

I use Perfect Disk on non-Vista systems.
Purchased license but have not yet installed in Vista.