Incremental drive backup

Discussion in 'Acronis True Image Product Line' started by Howard Kaikow, Mar 4, 2006.

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  1. Howard Kaikow

    Howard Kaikow Registered Member

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    In the last day, or so, I create a full system backup task, using drives, not files. The full backup and verify took a bit less than 3 hours.

    Yesterday, I ran an incremental backup task, using drives, not files, against that full backup. The copy took about 56 minutes and the verify took about 39 minutes. This was longer than I would normally expect.

    So, I almost immediately added 1 file to C:\, and again ran the same incremental backup task, expecting that a single file being added would result in a rather quick incremental backup.

    I was astonished that the copy again took about 56 minutes and the compare again took about 39 minutes.

    Is this the expected behavior?

    Is there a way to make the incremental backups finish faster?
     
  2. rbmorse

    rbmorse Registered Member

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    Howard, you're working in the disk mode rather than just with files. An incremental backup, even one involving just one changed file, still includes all of the normally hidden file system overhead stuff on the disk that changes every time the O/S hits it. There is apparently a lot of it and it doesn't look to me like it is very granular.

    A file mode incremental backup will perform a bit more like you expect. I think Acronis' compression routine works by sending each individual bit of data off to HQ via FEDEX ground for processing by hand but that is a different discussion. And, of course, a file mode incremental backup is even further removed from a true disc image than the disk mode incremental.

    Drive mode incrementals on Microsoft file systems seem to carry a lot more overhead than I see in drive mode incremental on the RiserFS partitions on my Linux drive.
     
  3. Howard Kaikow

    Howard Kaikow Registered Member

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    Yes, but the MFT, FAT, etc.stuff will only have changed on the drive on which I added the file. And even if all that stuff was included again for each drive, it should not take so long. In my test case, 9 of t e10 dries are NTFS, but I added the file on the small FAT 32 C drive.

    One of the issues with so called drive image backup is how to do incremental backups.

    Ghost does it very badly, but that's another topic. However, I'll menton that Ghost uses a mechanism that constantly monitors your drives IF YOU USE A RECOVERY POINT SET. This likely speeds up an incremental backup, but significantly slows down the system during normal operation. I am hoping that the new Norton Save and Restore will do things right. Alas, since SAve and REstore appears to run only on win XP, i'll not find out because I use win 2000. SAve and Restore is obviously intended to be a TI killer.

    I expect that (fortunately) TI is not using such a mechanism and has to figure out what to backup when it actually does the incremental backup. I sure don't want tI to add the overhead used by Ghost.

    In most cases, the extra (in terms of what I see with Retrospect) time used by TI for an incremental is no big deal as I oft run the incremental just before I go out to run errands or eat or whatever, but there are times when one really does want a quick incremental backup before moving on to other things.

    The surprising thing was that a very small change took just as long to backup as a much larger change.

    I sure hope so.

    In another thread, I asked whether a file mode incremental has to be based on a full file backup, or can it be based on a full drive backup.

    If the latter, then I'll give it a shot.
    If the former, ferget it!
     
  4. Acronis Support

    Acronis Support Acronis Support Staff

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    Hello Howard,

    Thank you for choosing Acronis Disk Backup Software.

    Please be aware that when Acronis True Image 9.0 creates an incremental image it analyzes all previously created images (initial full image plus a number of incremental images) and compares their contents with the contents of a disk\partition that is being backed up. Please also note that when Acronis True Image 9.0 verifies the integrity of the multivolume image archive consisting of the initial full image plus a number of incremental images it analyzes the whole set but not the latest incremental image only. However, less changes made to the hard drive since the last full or incremental image has been created should result in a lesser incremental image creation time and size.

    Could you please check each partition of all your hard drives by Windows utility?

    - For Windows 9x please use Windows menu Start\Run then enter the command "scandskw" and test all drives;

    - For Windows XP please use Windows menu Start\Run, then enter the command "chkdsk c: /r" "chkdsk d: /r" for every partition of your hard drive.

    Note that you will need to reboot your computer in order to scan the system partition.

    Please create new full image and several subsequent incremental images then and see if the problem still persists.

    If the problem still persists then please provide us with the following information:

    - Create Acronis Report and Windows System Information as it is described in Acronis Help Post;

    - What exact version and build number of Acronis True Image 9.0 do you use?

    You can find the full version name and build number by going to Help -> About... menu in the main program window.

    - What are the exact sizes of the initial full and several subsequent incremental images that you have created?

    - How much time did it take to create each image exactly?

    - Where do you store your images?

    Please submit a request for technical support. Attach the collected report.txt file and information to your request along with the step-by-step description of the actions taken before the problem appears and the link to this thread. We will investigate the problem and try to provide you with the solution.

    Thank you.
    --
    Alexey Popov
     
  5. Howard Kaikow

    Howard Kaikow Registered Member

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    I realized that.

    In my case, I ran the incremental. As soon as it was done, I added a single file, and ran other incremental, so I expected the 2nd incremental to run faster.
    chkdsk/scandisk is irrelevant.
    Disk fragmentation would be relevant.

    I fully defragged the drives a few weeks ago using the trial version of Perfect Disk.

    Subsequenly, I got TI and have installed/uninstalled TI with (lack of respect) to certain problems I've reported in other threads.

    Yesterday, I received, and installed, the retail verion of Perfect Disk. After, I reread the manual (yes, I am one reads manuals!), I'll again defrag the drives, which should help somewhat.

    However, fragmention of the TI backup set is likely also an issue.
    It would be rather a nuisance to have to run a defrag on the backup drive after each backup.

    I have three USB drives, two have a 2 MB cache, the other 8 MB, so fragmentation is likely worse with the former.

    I'll do it again after defragging all the drives. At this time, I will not be defragging the backup drive after each backup.
    This is NOT an issue for tech support.
    I'm just reporting behavior, and wondering whether others see the same behavior.

    Note that the design of TY's implementation would, by its very nature, be prone to excessive fragmentation.

    Writing a single file for each backup is more prone to fragmentation, and less robust, than writing a single file for each drive.

    Hmm, OK, I'l do the following experiment.

    Using the USB drive that has an 8MB cache, I'll use Perfect Disk to defrag the drive. There are 3 incrementals + the base backup.

    Then I'll do an icremental, see how log that takes.
    Then add 1 file, do an incremental and see how long that takes.

    I'll be back ...
     
  6. Howard Kaikow

    Howard Kaikow Registered Member

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    I have discovered one reason for the poor performance of the verify operation.

    Verify is using the pagefile, even tho there is more than enough free physical memory to obviate the need for using the pagefile.

    There's more than 300MB of memory unused.
     
  7. Acronis Support

    Acronis Support Acronis Support Staff

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    Hello Howard,

    I've just contacted our Development Team regarding this issue and they assured me that this problem is not related to Acronis software. The point is that Acronis True Image 9.0 has no ability to use Windows paging file or affect it's usage in any way. We advice you to contact Microsoft Support Team for further details.

    Thank you.
    --
    Alexey Popov
     
  8. Xpilot

    Xpilot Registered Member

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    Is that a threat or a promise :))

    Xpilot
     
  9. Howard Kaikow

    Howard Kaikow Registered Member

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    Ayup, page file use could be a result of windoze memory management, but trying to reproduce the problem is likely mission impossible. Of course, TI could be doing something that triggers this behavior.

    When I run a backup, I disable NAV's autoprotect and do not run anything else, so the environment is fairly constant each time I run a backup.

    If I remember, I'll do a full system file backup tonight to see what happens.

    Hmmm, or maybe i'll start a full system file backup this morning to observe the pagefile ans memory use.

    I'll let y'all know the result.
     
  10. Howard Kaikow

    Howard Kaikow Registered Member

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    "fair warning"
     
  11. Howard Kaikow

    Howard Kaikow Registered Member

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    Well, denial is not a river in Egypt.

    It is rather simple to demonstrate the problem, and that it is due to TI.

    First, I'm talking about FILE backup, NOT drive backup. If you made this clear to whomsoever you spoke to in development, then you need to find a more experienced developer, or, per chance, did some 3rd party write the file code for Acronis and your developers do not know how the code works?

    Here's how I reproduced the problem:

    1. I defined a task that would do a FILE backup of all 10 logical drives on my 3 internal hard drives.

    2. I rebooted the computer.
    3. Using Task Manger, Peak was 326992 a few minutes after reboot,
    4. Disabled NAV's AutoProtect.
    5. Started TI 9.2337.
    6. Peak rose to 337744, quite acceptable for starting TI.
    7. OK, I hope you are sitting down for this.
    8. I started the task to do the FILE backup.
    9. Peak quickly shot up to 929308, the Limit is 936340.
    10. Total dropped to a bit over 927000, then to around 877636, and stayed there.
    11. I cancelled the backup task and Total quickly dropped to 315692.

    Clearly a TI problem, surely some developer must know how the software works.
    If the software was from a 3rd party, you folkes sure better find out what's going on.

    I should mention that I use windows 2000 SP4.
     
    Last edited by a moderator: Mar 10, 2006
  12. Howard Kaikow

    Howard Kaikow Registered Member

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    Just installed TI in another Win 2000 SP 4 on the same PC. Same problem.

    Had my sister install TI on her Win 2000 SP 4 system. Same problem.

    I'd say there's a bug in TI that occurs in at least Win 2000 SP4.
     
  13. Howard Kaikow

    Howard Kaikow Registered Member

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    I Just stumbled upon further info indictating the problem is with TI.
    I'll post more later.
     
  14. Howard Kaikow

    Howard Kaikow Registered Member

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    Clearly a TI problem.

    If I reboot, disable NAV Autoprotect and start TI, the Total memory used (according to Task Manager) is about 307980 KB.

    I then created a script that backs up only the C and H drives using a FILES, not drives, backup.

    Running that script, Total memory quickly jumped to about 454000 KB. At completion of the script, Total memory was 545072 KB.

    This indicated tat the problem was a function of the number of drives to be backed up in the script.

    I then changed the script to include the C and H-M drives. Running the script caused Total memory to quickly jump to 766784 KB. I then cancelled the script.

    I then changed the script to include only the C drive. Running the script caused Total memory to jump to 393440 KB, but was very slowly increasing. Do not know what would have been the value if I had allowed the script to complete.

    Clearly, TI is making initial memory requests that depend on the number of drives included in the script. So that part is a TI problem. It is TI that is requesting the increased memory.
     
  15. Acronis Support

    Acronis Support Acronis Support Staff

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    Hello Howard,

    Could you please provide us with the following information?

    - Reproduce the problem on any of your computers and make the screen shots of Windows Task Manager illustrating the issue;

    - Create Acronis Report and Windows System Information for this particular computer in the way described in Acronis Help Post;

    - Where do you store your images?

    - Download the latest version of Acronis drivers, install it with disabled logging, try to create a file-based backup once more and inform us about the result;

    - Describe actions taken before the problem appears step-by-step.

    Please also make a screen shot of the Device Tree application:

    - Download and unpack the Device Tree application;

    - Run the application;

    - Completely unfold the \Driver\Disk and \Driver\FtDisk branches;

    - Move the margin to the left in order to see all the items;

    - Make a screen shot;

    Note that the application may crash the system when you exit, so we recommend you to save all your work and close other programs prior to running it.

    Please submit a request for technical support with the subject indicating that you want to contact Alexey Popov. Attach all the collected files and information to your request along with the link to this thread. I'll forward this issue to the appropriate person and he will take care of it as soon as possible.

    Thank you.
    --
    Alexey Popov
     
  16. Howard Kaikow

    Howard Kaikow Registered Member

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    I've already posted all the info you need in this thread, and the problem has been reproduced on 3 Win 2000 SP4 systems.

    You folkes should be able to reproduce the problem with the info already given.
     
  17. Howard Kaikow

    Howard Kaikow Registered Member

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    I've already cited examples and given you enough info to reproduce the problem.

    You already have that for bug report 511103.

    External USB drives.

    If I get a chance, but I just downloaded build 2337 on 2 March 2006,so I expect that I already have the latest drivers.

    Already described in this thread.

    No, I'm not going to take a chance on a crash, no time to deal with that.
    And it is pointless as the problem has been reproduced on 3 Win 2000 SP4 systems.

    When I take the time and trouble to report a problem, especially an easily reproducible problem in a forum momitore by the software vendor, I will not waste my time resupplying the info.
     
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