Incrementals suddenly way too large
Over the last week or so, my incrementals have become huge. I take a full backup (about 250 GB) and then 9 incrementals, followed by another full.
Just now, I took an incremental backup from yesterday's full (about 18 GB), and then immediately started another incremental (14 GB). In the past I might have a couple hundred megabytes, but now they are much much larger, even though I really haven't done anything since the previous backup. In reality there should be almost nothing in the second backup, since almost nothing has changed (I think) in the 10 minutes between incrementals. There's no way I have 14 GB of changed files in 10 minutes.
Is this a known issue? Is there any way to see what is in these excessively large incrementals, just in case there is something going on with my system in folders I might want to be excluding?
I've had the Creators Update for quite a while, easily predating this issue.
I see no smoking guns in the log using the utility you linked. I don't believe I have automatic defragmentation going on, certainly not with any third party software. If it's happening, Windows is doing it.
Here you can see the recent backup history (attached). You can see the sudden and dramatic increase in the size of incrementals.
There is definitely something going on with your source data on your computer given some of the sizes of your incremental backup files, starting on 5/22/2017 at 8:57PM when you show a 57GB file followed by a further 22GB less than 24 hours later. As to what is the cause of these very large incrementals I personally have no idea. You have not said what the source data actually is, the types of files involved etc, but given your full backup file sizes of over 200GB and growing larger, i.e. your screen shot shows full backups starting at 217GB, growing to 218GB then to 243GB over the space of 12 days, so whatever is causing the growth is affecting all backups, not just the incrementals.
I would recommend using a utility such as TreeSize Free to look at where this growth in file size is happening, perhaps mount some of the earlier full backups to drive letters then compare the size with your source data today?
I haven't said what the source data are because I have no clue where to even begin to suspect. I'm not doing anything that could or should be causing this as far as I can tell. I can account for the first huge incremental on 5/22 -- I downloaded a massive patch to Elder Scrolls Online (so the 50+ GB incremental there didn't surprise me). But even when I exclude all the directories where it is installed or puts data, everything after that is huge -- even if I never accessed the game or did anything to download stuff. (I even disabled networking to see if that would stop the massive incrementals, but it did not.) Incrementals usually used to run for about 1-2 minutes -- now they all run for 15 minutes or more.
Frankly I think it is a significant shortcoming of this software if you can't look at a particular backup set and see what it actually did in terms of the files it backed up -- because that would go a long way to tell you where the problem is.
[Edit to add -- just took another incremental. 95 GB in three hours and I've done very little!! That is unusable. I'm going to have to give up incrementals until I can figure out what the heck is going on.]
Next step is to archive my last good full backup, wipe the backup drive cleam and create a new backup set. I'm at a loss with respect to what else to try. This is not sustainable.
I am not sure that I can offer you any more help for this question other than to repeat the suggestion about using TreeSize Free to check where the size of data in the backups shows as being significantly larger.
I have no experience with online role playing video games as this is not an area that I have any interest in. If the incremental backup size continues to increase even when all networking is disabled, then this would suggest that there is an active background process on your system, which would concern me given the threat of malware doing bitcoin type data mining using system processes hijacked for this purpose. I would recommend using an offline antivirus scan utility such as the AVG Rescue disc which can be created on CD or USB stick and will scan your drives completely outside of Windows.
Another tool is the Microsoft Windows Defender Offline utility
It sounds like there could be some constant logging or caching going on to something that is being backed up. Open up the Task Manager and look at the Performance tab. Is the disk activity high? My system disk is bouncing between 0% and 1% while I'm being idle. Take a look at the Processes tab, make sure the Disk activity is shown to see who may be doing the writing. Hopefully this will lead to a culprit.
I've just discovered something. When I take a backup, the available space on my C: drive drops from 358 GB to 340 GB. And each incremental usually takes about 14 GB. Nothing else seems to be changing. When the backup is ending, the space reverts to 358 GB.
Is there something in this product that may be producing temporary files or folders that are being backed up when run? I don't see anything on the C: drive that can account for this on File Explorer, and I do have it set to show hidden files.
Very little disk activity when idle.
ziggy29, this is normal and is caused by Microsoft Volume Shadow Copy Service (VSS) creating snapshot data on your drive (using the System Volume Information folders / System Protection space). This space is only used for the snapshot and is not included in your backup image files.