Vista - over compensated

I set up winxp sp2 home version
on virtual pc with great success.

I set its ram to be 512 and
its partition to be 80 gigs.

further, I set the physical
partition for the virtual o.s.
to be 80 gigs as well.

the stats above are similar
to a physical disk drive slaved
on this machine with that o.s.


however, I noticed that perhaps
I overcompensated with
allocating 80 gigs for
both the virtual partition and
the physical partition.

maybe 40 gigs for both would
have been reasonable but like
hair cuts, its best to have more
than to be short.

since I have a strong feeling I
won't be utilizing 80 gigs of
physical partition, can I shrink
it to 40 gigs?

however it seems reasonable that
it won't harm the virtual o.s.

the concern I have is that
I don't want to reinstall the
o.s. and then get it reactivated
and then redownload all the
updates again.

thanks.

" db ·´¯`·.¸. .><)))º>." <databaseben via hotmail> wrote in message
news:BEE847B2-3E19-4BAB-8E5C-E2AE3B7E9CCB@xxxxxx
You created a separate partition? Why...?


--
Mark Rae
ASP.NET MVP
http://www.markrae.net

for safety purposes.

I actually already had
the extra partition anyways.

at this time the two vh files
are on my partition z and it
is 80 gigs.

however the space being
used by the virtual files are
about 5 gigs and growing.

but I don't think I will ever
grow to be more than 40 gigs.

so, would I be correct in
thinking that shrinking
z from 80 to 40 will de stablize
the virtual o.s.

"Mark Rae [MVP]" <mark@xxxxxx> wrote in message
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" db ·´¯`·.¸. .><)))º>." <databaseben via hotmail> wrote in message
news:0261670B-9C65-4A3F-B6D2-CAC2CFF39EAC@xxxxxx
Safety purposes...? Do you install every piece of software (e.g. Word, Excel
etc) on a separate partition...?
It will make not the slightest difference... VPC is just an application like
any other application...


--
Mark Rae
ASP.NET MVP
http://www.markrae.net

On Sat, 6 Dec 2008 11:26:06 -0600, db ·´¯`·.¸. .><)))º>. <databaseben
via hotmail> wrote:
If you have put the VPC files (*.VMC and *.VHD) on a physical
partition on your host which is not used by anything else (which is
what I believe you are saying) then you did something un-necessary...
The two files are just data files on the host system and can reside
anywhere you like on the host.

It has been recommended (but only for *performance* resaons) to put
the VHD file on a separate hard disk drive from the one which holds
the operating system of the host, though. The reason for this is that
the host operating system and the guest operating system both need to
read/write data constantly and if the VHD file is on the same hard
drive then the read head arm must constantly jump between the two
positions on the disk, slowing down the system.
But if there are two *physical* hard disks for the operating system of
the host and the VHD virtual disk file used by the guest, then the
need for "jumping" is removed and the system gets faster.

Notice that just creating a separate partition on a big single dtive
does not help! It is still the same read head arm that needs to move!
It might even make it worse because two partitions are guaranteed to
be far away in the disk surface whereas files in the same partition
can be closer...

--

Bo Berglund (Sweden)

thanks for the info.

but respectfully, I don't agree with the thoughts
about the disk arm as it was engineered to move
back and fourth from the beginning to the end of
the disk with assurance.

if however, there was a legitmate concern about
over working the arm,

then the engineers should not have developed large
harddrives.

otherwise, disks that are 90% full of data would
crash and burn, especially during indexing and
checkdisking and with opening files and programs
that may be located on the far end of the disk.

in any case, I am very pleased to have created
the additional partitions and have stored the
virtual o.s.'s on them.

I would firmly suggest a similar set up whenever
possible.

thanks again for replying and providing some
of your feedback. it was very kind of you to
do so.



"Bo Berglund" <boberglund@xxxxxx> wrote in message
news:knsmj4ljdnkj89rfk6ifrosp04b4lr8plh@xxxxxx

On Sun, 7 Dec 2008 09:56:01 -0600, db ·´¯`·.¸. .><)))º>. <databaseben
via hotmail> wrote:
You did not get the message....

What I was saying is that if the virtual machine's hard disk file (the
VHD file) is placed on the same hard drive as the host system is
running from, then one and the same hard drive will be involved in the
reading and writing of data for *both* the host operating system and
the virtual machine's operating system. Both of these accesses will
happen interleaved and at all times.

Now, imagine you have a single physical hard drive that has to switch
between reading the data for the virtual machine (from its VHD file)
and the host system data (Windows disk operations) at a very high
speed. What will happen is that the disk drive will go back and forth
from one location to another very rapidly, but the speed is now
limited by the arm having to go across the disk surface (a mechanical
movement with limited speed). THis is longer if you have partitioned
the drive to two logical drives.
What will happen is not that the drive will deteriorate in any way,
but the farther apart these areas are on the disk surface the longer
the traverse time will take and consequently the lower data rate you
will get.

Compare to the case with two physical disks where the operating system
is on one and the VHD file on the other. In this case the disk arms
(there are now to of them) can stay basically stationary on each drive
and the switch between operating system access and virtual machine
access is instantaneous in this respect. You still will have cylinder
rotation time to account for, but that cannot be avoided.

This is one reason for having the guest and host "disks" on different
physical hard drives.
Another one is if you place the VHD file on a USB2 connected external
drive then you have an easily portable virtual machine. You can carry
the USB disk to another computer rnning VPC2007 and use it there. But
that is another story.

I never said anything about harming the drives!

--

Bo Berglund (Sweden)

oh, I see now!

yes, I agree with you as
well.

thanks.


"Bo Berglund" <boberglund@xxxxxx> wrote in message
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