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timofcourse
Enthusiast
Enthusiast

Split vs Single Virtual Drive

We're making the move from Virtual PC to VMWare workstation to run a server environment (Windows 2008 R2) on our laptop for software demonstrations. I was hoping to find our more info as to why the installer says using Split disk images is recommended if the image is going to be moved to other computers.

Not knowing much about the VMWare technology my assumption is the advantages of using split disks would be that you could potentially divvy the disk files up over multiple drives (therefore potentially increasing performance) and "better" for copying only for the reason that if your copy fails you dont have to copy an entire 10GB file (for example), only the last 2GB files that werent copied yet.

Is my assumption correct here or are there other benefits to keeping split files for drives? We do plan to move them around between laptops and as we currently do today with a single vhd file for VirtualPC, we'd prefer to keep it a single file if there are no performance differences.

Thanks a bunch!

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AndreTheGiant
Immortal
Immortal

Split files are very useful to put them on filesystem with file size limit (for example 2GB for each file in FAT32).

But to have better performance you can use monolithic and preallocated disk.

Andre

Andrew | http://about.me/amauro | http://vinfrastructure.it/ | @Andrea_Mauro
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continuum
Immortal
Immortal

here is a comparison - check yourself

http://sanbarrow.com/vmdk/monlithicversussplit.html

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Do you need support with a VMFS recovery problem ? - send a message via skype "sanbarrow"
I do not support Workstation 16 at this time ...

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timofcourse
Enthusiast
Enthusiast

None of the "positives" mentioned in that chart for the 2GB split are really beneficial in our scenario. it also doesnt touch on my only two concerns: management and performance. I'd rather move around a single 30GB file than manage 15-2GB files if there are no downsides to performance and maintenance of the virtual machine.

Are there any comparisons of performance to show one option is superior to the other when hosted on a single hard drive?

Thanks again.

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continuum
Immortal
Immortal

if performance is your concern use preallocated ones - doesn't matter much wether you use split or monolithic.

I assume using monolithic only makes sense if you can create them on a fresh blank disk - if the disk is

already quite populated a monolithic will probably be fragmented in pieces anyway. In this case you can not defragment it easily.

What does managability mean ? - a 30 Gb one pice preallocated vmdk maybe easy to manage - its two files only but as soon as you have to copy it to a DVD or move it over the network split preallocated vmdks are easier to handle ....

As you see there really is no best choice

___________________________________

VMX-parameters- VMware-liveCD - VM-Sickbay


________________________________________________
Do you need support with a VMFS recovery problem ? - send a message via skype "sanbarrow"
I do not support Workstation 16 at this time ...

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