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csosza
October 22nd, 2007, 10:46 AM
Hi,

I did the followings (I have ATI Home 10)

(1) A full backup up of my C drive: the result is ~4GB, OK (name: MyBakcup)
(2) Installed program "A" and make an incremental backup: the result is ~75MB, OK (name: MyBakcup1)
(3) Installed program "B", and restore C drive from "MyBackup1"
(4) Installed program C, and make an incremental backup: the result is 4GB. Why? Im expecting again ~100MB. Is there any solution? I also checked the Options/Restore and unchecked "Set current date and time for restored files"

Thanks

seekforever
October 22nd, 2007, 07:43 PM
You did a restore of C before the last incremental. When TI puts data back on the disk it does not put all of it exactly into the sectors the data was taken from. In other words, the data originally in sector ABCD may now be in sector WXYZ.

Images are done based on an in-use sector bitmap. Restoring resulted in a vastly different bitmap and thus the large backup. Moving sectors such as is done in a defrag operation will also cause this to happen. The data hasn't really changed but is in a different place. However, this looks like a change to an imaging program.

Brian K
October 22nd, 2007, 08:13 PM
-{ Quote: " In other words, the data originally in sector ABCD may now be in sector WXYZ.
" }-
seekforever,

I agree with your defrag example but I'm not sure about the above.

With the Ghost apps, if you are taking daily incrementals and restore to one of those incrementals, the next incremental is appropriate in size. As if nothing had happened. I can't speak for TI.

seekforever
October 22nd, 2007, 08:34 PM
-{ Quote: "... With the Ghost apps, if you are taking daily incrementals and restore to one of those incrementals, the next incremental is appropriate in size. As if nothing had happened. I can't speak for TI." }-

Hi Brian K,
I'm always willing to be corrected but I think I'm right. I believe this situation has come up in the past and I'm aware of the issue of defragging a disk, making an image, restoring the image and the disk no longer being cleanly defragged.

Anyway, perhaps some others will join the discussion.

MudCrab
October 22nd, 2007, 09:08 PM
As far as I know, after ANY TI restore, the next incremental or differental will be larger than normal or as large as a full because most of the sectors have changed.

The only way to get the incremental back down to normal size is to do another full after the restore and base future incrementals on that instead of the old full.

Brian K
October 22nd, 2007, 10:16 PM
seekforever, I guess my point was that your explanation doesn't necessarily apply to other imaging software. It may apply to TI. The incremental image following a restore of a Ghost incremental image is no larger than the other incrementals.

I've mentioned before that TI does incrementals in a different way to Ghost and they tend to be larger. Ghost incrementals average about 1.5% the size of the baseline image. As long as you don't defrag, they remain at that size. After a defrag the first incremental is about 6% of the baseline size.

Different software, different behavior.

seekforever
October 22nd, 2007, 11:25 PM
-{ Quote: "... Different software, different behavior." }-

I won't argue with that!