ATI 2020 backup is... too small?
Hello everyone!
I just did some testing with an older Windows NVMe. My endeavour was to compare the difference the compression level makes in resulting file size, because the tables here (/content/16791) weren't extensive enough for me. I imaged only the WINDOWS volume, since I don't need it to be bootable and just wanted a ususal set of files.
However, I found that using compression level none yields a way too small backup.
According to Get-PSDrive, the volume has a size of 93,15GB; TreeSize reports 97,3GB to be in use. I also ran checkdisk to make sure Windows is not counting something wrongly.
When I now create an image of the volume using Acronis, compression level set to none, file exclusions deactivated, I get a size of only 49,68GB. How can that be?
As far as I'm aware, True Image doesn't do deduplication, block- nor file-level and, as I would interpret the table linked above, using compression=none should return a backup of the same size as the original (plus overhead), so why is the resulting image only about half the size of the original?
TI states 102,1GiB at "Data to recover" and 47,4GiB at "Backed up" in the Activity tab.
When I do the same image but with file exclusions activated I get 49,59GB, and with exclusions and normal compression level 49,64GB.
I created a new task with the same settings, no compression, no exclusions, thrice and it always resulted in the same 49,68GB±15MB.
All values labeled with GB are GB, not GiB. However, I'm not sure about the values in the activity tab, since, when chossing the backup source, Acronis uses GiB, but 102,1GB data to recover seems too high already, and it being GiB would result in about 110GB, but maybe it's counting the blocks instead (but for that I get 106,02GB used, which is close, but still not on point...).
pagefile and hiberfil were already deleted manually so won't make a difference with the exclusions.
I'm using ATI2020 Build 25700.
Thanks for any help in advance, maybe I'm overlooking something!
Darn it, I read through that article so many times but didn't attribute it to setting it to "none"...
I somehow interpreted the line as "I can't change how strong the compression is", but I wouldn't have thought that I can't even turn it off😅
Had I remembered that line earlier, it would have spared me of a lot of repeated backups.
Thanks again Steve, you're a lifesaver!
P.S.: But you must admit, when one searches for how the compression is handled and finds the article at kb.acronis.com/content/16791 (sorry, can't post links), which specifically applies to ATI2020, which doesn't use tib as standard anymore, and even mentions what compression library is used for "the new archive format", all while listing the percentages that are to expected for each level, one can trip over that😄
James, the only explanation I can offer about https://kb.acronis.com/content/16791 is that the opening sentence of the document states: (my emphasis!)
Acronis products save backup data in the proprietary TIB format using compression that reduces the amount of storage space needed for backups.
As such, the above does not apply to the new TIBX format! This could be 500% clearer with a simple statement to the effect that * Does not apply to TIBX format files in 2020! or similar.
Right again! Kind of weird is that they use ATI2020 as example for the different percentages in the first table, though - that was what lead me to believe the article applies to what I'm doing in the first place.
But I guess since the options aren't available for the tibx, even with 2020 only a table about tib is sensible.