Partial File Updating + USB drive

[zim2323]

I am a Windows 7 64bit Trial version 5.32 user hoping to find a better alternative to ViceVersa.

So far I am impressed. The one option that I'd really like to start using though is Partial File Updating. I have HUGE VMWare VMDK's (virtual disk images) that average anywhere from 20-75gb. The largest I have is around 97gb, smallest is 4gb.

I sync all of these VM's from my home PC to my a 1.5TB USB3.0 external hard drive for backup purposes. If I boot up a VM, using the 97gb one as an example, the ENTIRE 97gb has to be rewriten to the backup drive. I was hoping to use Partial File Updating to cut down both the time and the wear and tear on the external drive.

So far my experience has NOT been good on that front and wonder if I'm doing something wrong. All checksums have been created. As an example, I booted my 97gb VM and then immediately shut it down. This would mean that changes would be minimal. The logs show that Partial File Updating WAS used, and that it only "updated" approximately 100mb. This is great! However, it took just as long to copy that 100mb as it did the 97gb.

Maybe I am misunderstanding the process, but I don't understand why writing 100mb would take as long as writing 97gb. Can anyone explain to me what I am missing?


Thanks!!!

[M_Meyer]

Maybe versioning is active so the 97gb are copied to keep x old versions?

[zim2323]

No, versioning is disabled.

[superflexible]

Partial updating usually can only save time if you have a slow connection, such as a VPN or uploading via Internet. With a USB drive, it may not be able to save any time because it takes just as long to figure out which blocks have changed as to copy the whole file.