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Incremental Backups are too big

my scheme is that: 1 full backup and always incremental backups everyday when i shutdown the system.
The problem is that:
1. The incremental backups everytime, always if i dont create new file at all, are really big like at min 50gbs for each one.
2. I use a ssd nvme so dont start with saying i need to defrag because its 2022 and ssd do not defrag as hdd.

It's normal that aomei backupper, i have the paid pro version, arent able to do incremental only with real new or changed files?
Do aomei backupper dont understand ssd at all?
Do i need to find a better and more useful solution?


  • @Gianmarco, Did you perform disk backup? File Backup? How much data did you back up?
    And, how many incremental backup versions are there?
  • I have the same problem. I'm using System Backup for the system SSD, and that one works fine, the incremental backups are very small, 20 GB/day, compared to the full backup that is 1.4 TB.

    For the other 3 SSDs in my computer I use Disk Backup. It produces a full backup of 3.4 TB for them, which is OK. What is not OK is that each incremental backup is always 2.0 TB in size, even when I make minimal or no changes to those disks.

    I'm running out of space on my 17 TB backup NAS because of this. When will this bug be fixed?
  • @Vnicolici, Did you select "sector-by-sector" way(under Options--Backup Mode) when you do the disk backup? And, Did you back up the three SSDs on one backup task? or separately create backup for every SSD?
    Btw, please confirm if you encrypt for the 3 SSDs.
  • edited August 2023
    Hello. Currently a backup is running which will take about 6 hours. Unfortunately, the application doesn't allow checking any backup settings while any backups are running. In fact, even when a backup is not running, not all backup settings can be checked for existing backup jobs, in particular there is no way to check the backup mode used for a defined backup. I regard this inability to check settings after a backup has been configured as another bug.

    -  As far I remember (since the application doesn't give me any way to check and make sure), I used "Intelligent Sector Backup", not the other option, "Make an Exact Backup". There is no "sector-by-sector" backup mode, whatever that means.
    - I used a single backup for all 3 SSDs
    - I don't use encryption for any the SSDs or the backup.
  • After looking a bit more through the application, it seems the Backup Mode is not a backup job setting, but an application setting. And it's currently configured to Intelligent Sector Backup.
  • Yeah, the user interface makes no sense whatsoever. I deleted the 3 SSD backup job, and I'll create 3 backup jobs instead, one for each SSD, to see if it makes any difference regarding the incremental backup sizes. While defining a new disk backup, it asks for the backup mode. But the backup mode also seems to be an application setting (or what the app seems to call global settings), independent of the backup job definition. There is also an option to save to global settings when defining the backup job, but that mentions only compression and splitting settings will be saved to global settings. Which again makes no sense. What are those global settings anyway? Defaults for new jobs? And what about the global backup mode setting? Is it a default for new jobs too? Or does it apply to all backup jobs, retroactively, when changed? If it does not, and is just a default for new jobs, then why can't we see the backup mode configured for each backup job after defining the backup jobs? Is it not part of the backup job definition, and just the global app setting is used, or it's just the UI hiding the information, and it's actually part of the backup job definition?
  • Oh, and another "nice" thing about the UI, if you switch to a different tab (for example Home) while defining a backup job, before saving it, it just discards all the work you did to configure the new backup job, without any warning.
  • @Vnicolici, Sorry that it indeed can't check the backup mode on the existing task. We will submit the situation to our dev team.
    global settings means that it will default retain the same settings when you create the next task.
    "I'll create 3 backup jobs instead, one for each SSD, to see if it makes any difference regarding the incremental backup sizes. "---Is there any update?

  • The backups are still in progress. I'll let you know.
  • edited September 2023
    Splitting the 3 SSD backup in 3 separate backups seems to have fixed the problem with the large incremental backup sizes, now the incremental backups are very small, as expected, for all SSDs.

    I have only one remaining problem now, the automatic cleanup is not working for my System Backup. Some background below:

    When the backup volume became full last week, due to the incremental backup for those 3 SSDs not working properly, the System Backup, which backs up my 4th SSD, the one containing my Windows installation, failed due to low disk space on the backup volume.

    The system backup is configured as an incremental backup, with a one full + 6 incremental scheme:

    At the time it failed, it has just reached 6 incremental backups, and was performing a full backup. Since the backup failed, after clearing some space on the backup volume, I ran it manually, and that was successful, it created the full backup that failed earlier that day.

    I've also configured automatic backup cleanup for all backups, including the System Backup, by quantity, to only keep the latest set. The problem is it doesn't seem to work for the System Backup (for the others it's too early, and I'm not sure if it will work when the time comes).

    So, at the moment, I have two sets of System Backups (the first one with one full + 6 incremental, and a second one with one full + 2 incremental), and it's not automatically deleting the first one:

    There is an additional element that may have been a factor. When I initially configured the System Backup, I enabled the option to create one full backup and always retain it before performing the scheme. Which resulted in 2 full backups being performed at the start of the scheme, instead of one. Which kind of makes sense, but it was not what I actually wanted. What I wanted was to be sure a full backup was executed before creating incremental backups, but that doesn't require this option, it's automatic.

    So, after running the backup a few times, at some point I unchecked the "create one full backup and always retain it" setting. But unchecking the setting didn't automatically delete the first full backup file, which I didn't need. So I deleted it manually.

    Could this be the reason it's not cleaning up the previous set? Or the fact that the full backup was performed manually when the disk became full? Or will it do it later, when the second set is "complete", when it includes 6 incremental backups too? Or do I need to rename the files so that the first one doesn't have a number at the end, and decrement the number for each of the subsequent files, since I deleted the unneeded full backup made initially and the sequence is now missing the first file? Or do I need to just delete the backup files and re-create this backup job to make it work properly?

    An additional question, what happens with the file number sequence during an automatic cleanup? Are the remaining backup files renamed, so that the numbers at the end are shifted down by the number of deleted backup files, or does the number sequence at the end just continue to grow forever?

    After reading the documentation a bit, it seems this part of the tasks2.2.xml file controls the cleanup:

    <Policy Type="8" TurnOff="0" SafeFirstVersion="0" Range="1" BaseVer="8" BackupMeansOpen="0" ClearType="0" ClearGroup="1" ClearGroupNumber="6" BackupLoopOpen="1" ClearOpen="1" ClearDayNumber="157681672" ClearWeekNumber="157682648" ClearMonthNumber="157683624" /><br>
    If I need to edit anything here to make it work, let me know.
  • @Vnicolici, Based on your backup cleanup plan, it will delete the first set of backups (1 full+6 increments) when the second set of backups(1 full+6 increments) have been completed.
    Because you have manually delete some backups and modify the backup plan, it might disrupt the backup version that needs to be deleted. Please try to delete all backups manually, then disable backup cleanup plan and click "OK" to save the configuration, then re-open backup scheme to set backup cleanup plan again. So, it will re-start the backup cleanup plan.
  • OK, for now I have enough space, so I'll just let run for a few more days, until it starts deleting backups, assuming it will happen at some point. Then I'll delete manually anything it might have missed. If it doesn't work, I'll proceed as suggested. Thanks.
  • So, I've been monitoring it for a while, the system backup finally started deleting old backups, but there is the initial set of full + incremental backups which it refuses to delete, I'll have to delete that manually at some point. It seems when you edit the cleanup settings, the older backups are then ignored, they apply only for future backups.

    The disk backups still randomly create huge incremental backups from time to time, for no apparent reason, but most of the time work they work properly and they also delete old backups as expected (keeping the last full set of backups and the last incomplete set of backups).

    The only other annoying thing I found is that reboots are blocked during backups. Last week I rebooted my computer while a large backup was in progress, and windows closed all applications and initiated the reboot. The backup application didn't attempt to stop the reboot or warn me that a backup is in progress.

    However, at some point, the reboot was blocked with this message:

    The problem is at that point I had some quite urgent work to do, and AOMEI was basically keeping my computer hostage, and there was no way to stop it. After waiting for about an hour for it to finish, the situation at work became so urgent that I had to force the computer to power down, before it was able to finish the backup.

    From now on I'll check before each reboot that no backup is running, to prevent being locked out from my computer for hours.

    Of course, I could have scheduled it to run at night, when it's less likely I'll need my computer for work, but still, this was not an optimal situation. And I'm concerned that if I change the schedule it will start ignoring old backups and not clean them again.

    Overall, the AOMEI software is acceptable, meaning at least it works, compared to the Microsoft Windows backup that was randomly failing, which is why I switched to AOMEI. However, the software still has quite a few rough edges. But I can live with it.

  • @Vnicolici, "I'm concerned that if I change the schedule it will start ignoring old backups and not clean them again."---You can modify the schedule time. 
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