[Info-vax] Backup restore system disk

[Jan-Erik Söderholm]

Den 2020-08-18 kl. 15:31, skrev Randy Hancock:
> On Monday, August 17, 2020 at 11:22:32 AM UTC-6, Dave Froble wrote:
> 
>> 
>> You might also want to consider whether your file which is a virtual 
>> disk is itself fragmented.  Defragmenting files inside the vdisk
>> won't help if the vdisk is fragmented.
>> 
> Hmmm... Is that possible?

My guess is, that the vdisk (the "container" file on the host system)
is more or less continuous, if there was enought continuous space
available when it was created. I do not expect the vdisk file to
move or split during normal use from the VMS side.

And also, I do not think that having a vdisk that is split in
a few pieces makes any real difference.

 > I understand the Vdisk being fragmented just like a physical disk
 > on another system we have,...

That is, another VMS system, right?

And yes, the *content* of the vdisk (as seen from VMS) will become
just as fragmented as any similary sized VMS disk. But in the other
hand, it is usually easy to just create a vdisk large enough (and use
the proper INIT paramaters) so that fragmentation becomes no isssue.

 > which I've dealt with easily in the past. But the Vdisk is only
 > accessed by the VAX system.

And regarding Davids comment, of course fragmentation on the VMS
side still have it's issues no matter if the vdisk itself is
fragmented or not.

I take it for granted that you have done some anayses that you
actually *have* a fragmentation issue?