Incremental is the same size as the full

I made two incrementals in a row and was very careful to spec them as incremental and based off the full image file name, and twice in a row in created incrememntals that were essentially the same (huge) size as the full backup. What's going on?

 

Hello Jaxx,

Thank you for choosing Acronis True Image (http://www.acronis.com/homecomputing/products/trueimage/).

Please make sure you have no special defragmenting tool launched or something like that. To make a clean experiment you may try to create images after booting from Acronis Bootable CD and compare them in Windows then.

Thank you.
--
Ilya Toytman

 

I like TI very much but yesterday I created an incremental image about 4 hours after I had created the full image. No defragg of course. The incremental was within 100 Megabytes of the size of the full image. Puzzling? It's no big deal but it means making incrementals is a waste of time. I'll test this again.

 

I deleted all my backups and started over and the incrementals were a very small fraction of the full backup. Maybe I appended to the wrong file name? I dont know but its ok now. Btw, just as a test, i did an immediate incremental to the previous incremental and it was even smaller, by far.

 

I saw this thread about incremental size problems and I decided to experiment a bit.

I booted with the Acronis boot CD and restored my system partition to the latest incremental.
Then immediately after that, I made a new incremental of the same partition (without booting into the OS) and the new incremental was almost the same size (about 90%) as the original full backup.

Could someone tell me why?
I would think that the partition I restored minutes before was exactly the same when I initiated the new incremental.

After this incident I booted into the system and mounted these two states of my system partition as virtual drives (I selected the latest time and the one before)
I had no tools at hand to compare them bit by bit, but the used space/ free space numbers on the drive properties page were showing identical values.

I repeated this process 3 times with the same results.
What's up?

 

Hello eclipse3337,

Thank you for choosing Acronis True Image (http://www.acronis.com/homecomputing/products/trueimage/).

The problem is that when you restore the image of a separate partitions sector content is restored but sector addresses may vary. It means that particular sector location after the restoration may change. In this case Acronis True Image will include this sector into image.

Thank you.
--
Ilya Toytman

 

Does it mean, that a restored partition is sector-wise not identical to the state of the same partition at the time of imaging?
(I was restoring the image to the original location on the disk every time)

 

If nothing changed on the disk why would the contents of a sector be restored to a different sector address? Of course if the restore is to a different disk, a partition elsewhere on same disk or the partition is moved on the disk then sector addresses would be different.

 

Hi tachyon42,

My explanation would be that, prior to restoring the original drive, TI needs delete the existing partitions. Therefore sector addressing could well be starting off from a different baseline to that from which the image was created.

Regards

 

Hello eclipse3337 and tachyon42,

If you deal with the data that is not sector-bound (this takes place for almost all the data you have) Acronis True Image doesn't watch for the sector accordance because it doesn't matter in fact where to restore the content of particular sector. This doesn't affect the functionality of all the applications after the restoration however.

Thank you.
--
Ilya Toytman

 

Hi Ilya,
If I understand it, this means that when a restore is done data may be restored to totally different sectors. Consequently the NTFS file structure may be totally different, files might be fragmented. So a partition that was defragged prior to the image creation might be restored in a badly organized way and would have to be defragged again.
I doubt this can be correct so I obviously haven't understood your explanation - would you please clarify.

 

Hello tachyon42,

You are right, the data (ecept the necessary system data that is bound to sectors) may be restored to different sectors. However, usually there are slight changes and it is unlikely that you get the restored drive in "total disorder". Still even the shift by one sector will result in Acronis True Image creating the incremental image of almost the same size as the previous one.

Thank you.
--
Ilya Toytman