>
>Hi,
>
>I would like to test my ideas, if they are wrong..
>
>I think defragmentation does not give so much gain
>as for real machines, if VD is small, compared to physical one.
>But it is still worthy to do it, at least plain file defragmentation.
>
>I think, if one uses undo disk on VPC,
>defragmentation could cause excessive work
>for later disk merging.
>Therefore it is good to postpone defragmentation
>until undo disk is merged, then cancel undo seeting
>launch VM and perform defragmentation.
>
>Am I right ?

>In article <(email address - cut out)>, bobcomer-
>(email address - cut out) says...
>>
>> >Am I right ?
>>
>> Pretty much. The only thing I'd add is that defragmenting a dynamic
>> disk is not a good idea, even if you don't have undo disks enabled. It
>> has the potential to balloon the size up quite a bit. If it really
>> gets heavily fragmented, then you should go through the procedure for
>> compacting the disk rather than just defragmenting it.
>
>I would use favorite JKDefrag with default settings,
>it compacts well in reasonable time.

>In article <(email address - cut out)>, noreply.-
>@-.essjae.com says...
>>
>> >
>> >I would use favorite JKDefrag with default settings,
>> >it compacts well in reasonable time.
>>
>> But, you would still need to compact the VHD. After you defrag, there
>> are additional steps to take to compact the actual VHD file. Defrag,
>> precompact, compact.
>
>Hm, interesting pointing out.
>
>I have obviously missed something, supposing dynamic disk
>would shrinking if compacted by defrag.

> On Tue, 3 Feb 2009 19:45:53 +0100, Poutnik
> <(email address - cut out)> wrote:
>
>>In article <(email address - cut out)>, noreply.-
>>@-.essjae.com says...
>>>
>>> >
>>> >I would use favorite JKDefrag with default settings,
>>> >it compacts well in reasonable time.
>>>
>>> But, you would still need to compact the VHD. After you defrag, there
>>> are additional steps to take to compact the actual VHD file. Defrag,
>>> precompact, compact.
>>
>>Hm, interesting pointing out.
>>
>>I have obviously missed something, supposing dynamic disk
>>would shrinking if compacted by defrag.
>
> it's a common misconception. Defragging won't decrease the actual
> size of the VHD file on the host, in some cases it can increase it.
> After you defrag it, you need to zero out the empty space (tool is
> included with VPC), and then compact it via the Virtual Disk Wizard in
> VPC)

>> > it's a common misconception. Defragging won't decrease the actual
>> > size of the VHD file on the host, in some cases it can increase it.
>> > After you defrag it, you need to zero out the empty space (tool is
>> > included with VPC), and then compact it via the Virtual Disk Wizard in
>> > VPC)
>>
>> Do you prefer that to sdelete?
>
> Well, sdelete was in the first place I was thinking about,
> when topic came to free space zeroing....

>
> >Am I right ?
>
> Pretty much. The only thing I'd add is that defragmenting a dynamic
> disk is not a good idea, even if you don't have undo disks enabled. It
> has the potential to balloon the size up quite a bit. If it really
> gets heavily fragmented, then you should go through the procedure for
> compacting the disk rather than just defragmenting it.

>
> >
> >I would use favorite JKDefrag with default settings,
> >it compacts well in reasonable time.
>
> But, you would still need to compact the VHD. After you defrag, there
> are additional steps to take to compact the actual VHD file. Defrag,
> precompact, compact.

>
> Steve Jain [MVP] wrote:
> > On Tue, 3 Feb 2009 19:45:53 +0100, Poutnik
> > <(email address - cut out)> wrote:
> >
> >
> > it's a common misconception. Defragging won't decrease the actual
> > size of the VHD file on the host, in some cases it can increase it.
> > After you defrag it, you need to zero out the empty space (tool is
> > included with VPC), and then compact it via the Virtual Disk Wizard in
> > VPC)
>
> Do you prefer that to sdelete?

>
> >
> > Well, sdelete was in the first place I was thinking about,
> > when topic came to free space zeroing....
>
> I like that I can script the defrag/sdelete sequence so I don't have to pay
> attention until it's done.