Some questions to ask...

30 Sep 2010

Hello again, sorry to bother as well.
But, I would like to ask, what would be the recommended RAM for my host PC to have before running on VMWare Workstation, VirtualBox or Virtual PC - SP1? I am currently running on 3 GB of RAM, Windows 7 Ultimate - 32bit and a Core 2 Duo.
I would like to use XP with 512 MB of RAM on my VM softwares so, just checking, which VM software would be better in terms of performances. I would only be using it to test-run some softwares and games.

Is 3 GB of RAM enough to 'supprt' XP with 512 MB of RAM on a VM? I did tried VMWare Workstation some times ago but I only have 2 GB of RAM and I must say, it's quite 'lag' when I were to switch over from host to the VM. And, from the last time I used, VirtualBox, it can only share file with host using a shared network rather than like VMWare or VPC's drag and drop into the VM's window itself.

Sorry for the newbie questions and the horrible English text-wall!!!

yowanvista · 30 Sep 2010

3GB is fine for VirtualBox with XP running 512MB RAM
If it is lagging you might want to add more RAM and upgrade to x64 as you won't be able to use more than 3.2GB

jimbo45 · 30 Sep 2010

Hi there
There's no RIGHT answer to this question as the number, content and size of your Virtual machines will matter.

RAM is probably THE MOST important consideration in running VM's -- you can get away with 3GB but I'd look on 4GB as a BARE minimum. Remember the HOST OS needs to have enough or your system will be doing nothing but paging -- and paging Virtual machines will KILL a system STONE DEAD very quickly.

Decent Disk speed is also important -- try and have your VM's on different DEVICES (and I mean different disks, not just on different partitions).

CPU isn't so much an issue at this point.

On a Laptop you can't do much about different disk devices but I'd still say go for a MINIMUM of 4GB RAM even if you only intend to have a fairly small XP Virtual Machine.

I have 16 GB of RAM on my main machine which allows me to run a load of VM's quite nicely.

Cheers
jimbo

30 Sep 2010

yowanvista said:

3GB is fine for VirtualBox with XP running 512MB RAM
If it is lagging you might want to add more RAM and upgrade to x64 as you won't be able to use more than 3.2GB

Yes, sir. VirtualBox is a sexy software but I don't like to use shared network in order to share files. I would prefer drag and drop into the VM itself. Rather than using shared network to share files. Or, is there a way around it?

Tbh, I just upgraded my RAM from 2 to 3 and I don't got much spare cash to grab another 2 GB of RAM to slot it in so, I might wanna' do that in the future. Thanks for the suggestion. :)

jimbo45 said:

Hi there
There's no RIGHT answer to this question as the number, content and size of your Virtual machines will matter.

RAM is probably THE MOST important consideration in running VM's -- you can get away with 3GB but I'd look on 4GB as a BARE minimum. Remember the HOST OS needs to have enough or your system will be doing nothing but paging -- and paging Virtual machines will KILL a system STONE DEAD very quickly.

Decent Disk speed is also important -- try and have your VM's on different DEVICES (and I mean different disks, not just on different partitions).

CPU isn't so much an issue at this point.

On a Laptop you can't do much about different disk devices but I'd still say go for a MINIMUM of 4GB RAM even if you only intend to have a fairly small XP Virtual Machine.

I have 16 GB of RAM on my main machine which allows me to run a load of VM's quite nicely.

Cheers
jimbo

Hi, I would like to ask again, by your meaning of get away with 3 GB of RAM, does it means that I can run a 512 MB of RAM smoothly? I have 2 HDD tho', do it mean that it'll be better to install my VM on different HDD from where the VM software is installed? Sorry for asking, just checking. I'm not quite sure whether which VM softwares to use and of course, like what you have said, it's hard to choose from which is the 'best' as it would depend on one's specs and all. Sorry for ignoring that into consideration when posting.

jimbo45 · 30 Sep 2010

Hi there
several issues here

1) you "Can get away" with 3 GB of RAM means that a minimal Virtual machine will run moderatly OK but don't try a 1.5 GB full W7 X64 Virtual machine.

Note that the host OS itself will need a minimum of 1 - 1.5 GB of RAM itself after you've allowed for the RAM allocated to the virtual machine -- and also you aren't doing too much on the Host OS at the time your Virtual Machine is active.

2) The Virtual Machine data file (in vmware its an *.vhd file) should be on a different Physical disk drive since the Virtual machine will be managing its own I/O which then gets "translated" to I/O requests on the Host file system (the *.vhd file). So you don't want to have all this disk I/O taking place on the same drive that the HOST OS is using.

If it is on the same drive as the main OS then you can get a lot of extra "Disk contention".

For running a smallish Linux or XP Virtual Machine then 3GB RAM "will do" but I think most people totally underestimate the amount of RAM Virtual Machines just GOBBLE UP to give them acceptable performance.

CPU is not normally a serious issue but people tend to upgrade a processor before looking at the RAM bottleneck.

While this can be good for the HOST system lack of CPU power is rarely an issue for typical Home computers running one or two virtual machines.

Remember --unlike other performance issues the golden rule is that Virtual Machines just EAT RAM for breakfast and until you get say around 6 or 8GB of RAM you'll always get some type of "laggy" performance.

Another suprprise here is that while 4GB RAM will run ONE 1.5 GB RAM Virtual W2003 server for example -- you'll struggle to get TWO operating concurrently with any sort pf acceptable performance-- a 6GB system will actually run 3 of these without a problem so you need to go over a certain minimum threshold of RAM to get acceptable Virtual Machine performance.

Getting good acceptable Virtual Machine performance on a 32 bit system is a serious challenge due to the addressing scheme. The Host can only see around 3.75GB Max so you are doubly screwed.

Anyway you can probably get some sort of perfotrmance out of a 512K RAM Virtual machine on a 3GB RAM system but don't run any more than ONE Virtual machine at the same time.

Cheers
jimbo

01 Oct 2010

jimbo45 said:

Hi there
several issues here

1) you "Can get away" with 3 GB of RAM means that a minimal Virtual machine will run moderatly OK but don't try a 1.5 GB full W7 X64 Virtual machine.

Note that the host OS itself will need a minimum of 1 - 1.5 GB of RAM itself after you've allowed for the RAM allocated to the virtual machine -- and also you aren't doing too much on the Host OS at the time your Virtual Machine is active.

2) The Virtual Machine data file (in vmware its an *.vhd file) should be on a different Physical disk drive since the Virtual machine will be managing its own I/O which then gets "translated" to I/O requests on the Host file system (the *.vhd file). So you don't want to have all this disk I/O taking place on the same drive that the HOST OS is using.

If it is on the same drive as the main OS then you can get a lot of extra "Disk contention".

For running a smallish Linux or XP Virtual Machine then 3GB RAM "will do" but I think most people totally underestimate the amount of RAM Virtual Machines just GOBBLE UP to give them acceptable performance.

CPU is not normally a serious issue but people tend to upgrade a processor before looking at the RAM bottleneck.

While this can be good for the HOST system lack of CPU power is rarely an issue for typical Home computers running one or two virtual machines.

Remember --unlike other performance issues the golden rule is that Virtual Machines just EAT RAM for breakfast and until you get say around 6 or 8GB of RAM you'll always get some type of "laggy" performance.

Another suprprise here is that while 4GB RAM will run ONE 1.5 GB RAM Virtual W2003 server for example -- you'll struggle to get TWO operating concurrently with any sort pf acceptable performance-- a 6GB system will actually run 3 of these without a problem so you need to go over a certain minimum threshold of RAM to get acceptable Virtual Machine performance.

Getting good acceptable Virtual Machine performance on a 32 bit system is a serious challenge due to the addressing scheme. The Host can only see around 3.75GB Max so you are doubly screwed.

Anyway you can probably get some sort of perfotrmance out of a 512K RAM Virtual machine on a 3GB RAM system but don't run any more than ONE Virtual machine at the same time.

Cheers
jimbo

Thank you for your reply and sorry for my delay in seeing this reply. Been outta' the country for somethings.

I understand now and well, tbh again, I don't have much spare cash around on this month so my best bet is that when I get enough money on a extra 2 GB of RAM to go for 4 GB of RAM and install a 64-bit OS then I can truly use the performance on them.

I have bookmark'd this page for my reference and once again, thank you for your time to reply and clarify my problem! THANKS!