[dba-Tech] VirtualBox Questions

Theoretically, 16 exabytes can be supported by a 64 bit hardware... now
reality. Check this out: http://en.wikipedia.org/wiki/X86-64

It is all so hardware architecture and OS dependent. I believe your Acer has
an internal 52bit bus and an AMD64 chip is 44bit and is therefore limited.
The new Windows 7 64 bit can access up to 196GB of RAM while the Vista can
access up to 128GB of RAM but this depends on the versions.

The new Snow Leopard from Mac is supposed to be a true 64bit OS. I
understand the Ubuntu 9.x, with the Ubuntu server header
(http://www.cyberciti.biz/faq/ubuntu-linux-4gb-ram-limitation-solution)
can be set to be able to access 16TB of RAM but this is all again, hardware
dependant.

I have never been able to get more than 4GB of RAM addressable on most
inexpensive 64bit motherboards and that would include Acer (32 or 64). That
is the reason I bought an Asus 64 bit quad core motherboard as it seems to
have no problem accessing 8GB of RAM (the maximum I could afford at the
time).

I am by no means an expert at this but these are my experiences. I have
found that the theoritical limit has nothing to do with the real limit.

HTH more than confuses.

Jim   


-----Original Message-----
From: dba-tech-bounces at databaseadvisors.com
[mailto:dba-tech-bounces at databaseadvisors.com] On Behalf Of Arthur Fuller
Sent: Saturday, September 19, 2009 4:26 PM
To: Discussion of Hardware and Software issues
Subject: [dba-Tech] VirtualBox Questions

I run Sun's VirtualBox on my AMD-64 bit box with an NVidia video driver and
a 22" Acer monitor and 4GB of RAM. For the most part, I love what I am
getting, but there is one funny thing that puzzles me. I have several
virtual machines installed: Ubuntu Linux, and two different instances of
winXP, one devoted to my Bitnami Rubystack installation and the other to XP
+ Office 2007 + various SPs. The latter opens in a relatively large screen,
but the Bitnami one opens in a smaller window which will not expand beyond
its initial size. I don't know what I did to create these differences, but I
would really enjoy figuring out how to increase the size of the Bitnami XP
VM.
Should I maybe destroy it and start over? I cannot remember what I did to
create the nice big XP window, but that's how I would like the BitNami XP
installation to appear in a window sized similarly.

These problems aside, and my ignorance about Hyper-V and other offerings
admitted, I really like Sun's VirtualBox. At the moment I am running two
instances of XP and one instance of Ubuntu, all on top of Windows Sever 2008
SP2, and everything works lovely. I am slowly concluding that this is the
way to go, in future: for every client project, a VM that emulates his/her
installation. Nothing wrong with a dozen VMs, only two or three of which are
running at any given moment.

(Another question, whose answer I suppose I can look up, but thought it
might prove fruitful to make it a public question: given four slots, what's
the maximum amount of RAM I can plonk into this baby? Are there 4GB chips?
That would take me to 16GB and doubtless that would be very cool in a
VirtualBox environment!)

And just to tie all this up, a segue back to the poetry thread, from T.S.
Eliot:

I grow old, I grow old,
I shall wear the bottoms of my trousers rolled.

A.

-- 
Semi-retired SQL guru, interested in interesting projects not YAFOES (yet
another friendly order entry system).
_______________________________________________
dba-Tech mailing list
dba-Tech at databaseadvisors.com
http://databaseadvisors.com/mailman/listinfo/dba-tech
Website: http://www.databaseadvisors.com