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I noticed slow disk performance running a VM in VirtualBox.

Filefrag shows 1204 extends for the virtual disk file.

I know file fragmentation only occurs when necessary, but i wondering if this is a correct value or if the file needs some kind of defrag.

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What filesystem are you using? – haneefmubarak Aug 4 '13 at 22:09

I suspect it is a dynamically allocated image, in which case it may grow in size over time and this may explain the many different extents you have for this file.

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the vdi file is not dynamically allocated – Vilain Mamuth Oct 16 '12 at 12:16

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