For laughs I installed Vista under VirtualPC with only 256MB RAM. And Huh!?! WTF

[turrican2097]

Vista 256MB
The screenshot shows 7zip benchmark using a 8MB dictionary and allocating 125MB out of the 256. Media Center, media player, device manager, computer properties and mahjong are also loaded

Very high performance. Maybe 80% to 90% of the performance you would get on VirtualPC, giving it 800MB

This is how I did it:

- Installed VirtualPC 32bit
- Installed Vista 32bit on a small virtual disk. Give it more memory for now. I gave 800MB.
- Installed the VirtualPC utilities
- The guest OS disk access is must cached by the host. Append "-usehostdiskcache" to the command line on the VirtualPC shortcut. The advantage is that VirtualPC only locks 256MB RAM and Vista obsessive disk swapping is avoided.
- A physical disk doesn't have to be high end. I used a Samsung IDE 1614N.

The nice thing is that anyone can do this and see for themselves 🙂

 

[reverend boltron]

:: nevermind ::

 

[Nothinman]

I'm not sure where the "WTF" comes in.

 

[Brazen]

My Ubuntu laptop flies with only 128MB RAM. WTF?

 

[turrican2097]

I really would like to know how the way I posted, makes the fact that I present more or less interesting

 

[Nothinman]

So you're just surprised that Vista runs ok with 256M of memory?

 

[dclive]

Originally posted by: turrican2097
Vista 256MB
The screenshot shows 7zip benchmark using a 8MB dictionary and allocating 125MB out of the 256. Media Center, media player, device manager, computer properties and mahjong are also loaded

Very high performance. Maybe 80% to 90% of the performance you would get on VirtualPC, giving it 800MB

This is how I did it:

- Installed VirtualPC 32bit
- Installed Vista 32bit on a small virtual disk. Give it more memory for now. I gave 800MB.
- Installed the VirtualPC utilities
- The guest OS disk access is must cached by the host. Append "-usehostdiskcache" to the command line on the VirtualPC shortcut. The advantage is that VirtualPC only locks 256MB RAM and Vista obsessive disk swapping is avoided.
- A physical disk doesn't have to be high end. I used a Samsung IDE 1614N.

The nice thing is that anyone can do this and see for themselves 🙂

80-90% performance compared to what, and doing what?

 

[Brazen]

Originally posted by: turrican2097
I really would like to know how the way I posted, makes the fact that I present more or less interesting

Were we supposed to laugh? oops.

ROTFLMAO

There ya go 😉

And welcome to ATF.

 

[turrican2097]

Originally posted by: Nothinman
So you're just surprised that Vista runs ok with 256M of memory?

Yes 🙂 It's strange due to the claimed requirements that I see everywhere on the net

Originally posted by: dclive80-90% performance compared to what, and doing what?

More less what I said above: "7zip benchmark using a 8MB dictionary and allocating 125MB out of the 256. Media Center, media player, device manager, computer properties and mahjong are also loaded". Please see the screenshot.
Compared to giving it more less 800MB, using hardware assisted virtualization.
Note though that when 256 stops being enough for holding the absolute minimum working set, 7zip drops to a few KB/s, because the system uses all the CPU for trashing. The thing is, the host is not affected by that, because all swapping that would hit disk, is properly cached. This is the great advantage IMO. I guess I really only need to give *enough* memory.

Originally posted by: Brazen

Originally posted by: turrican2097
I really would like to know how the way I posted, makes the fact that I present more or less interesting

Were we supposed to laugh? oops.

ROTFLMAO

There ya go 😉

It's irrelevant what you (Brazen), not the forum was supposed to do. I posted in good faith, do not intend to gain anything from it, and it is reproducible. I didn't expect personal posts so soon.
You are a very important poster as you are Diamond Member. That does NOT mean that I am wrong. Which btw is irrelevant because I do not care about advocating this. What I know is that VirtualPC needs physical memory which it locks, otherwise it will not start. I still testing if this suits my *personal* needs. I need a lot more mem for Windows XP SP2, VC+, Process Explorer, Adobe Reader, Opera, SDK Documentation, .NET, SQL Server Developers Edition, Visio, OpenOffice, mingw, wxPython, AntiVir...

Originally posted by: Brazen

And welcome to ATF.

Thank you. And forum, sorry that I didn't say hello on my 1st post

 

[dclive]

Originally posted by: turrican2097

Originally posted by: dclive80-90% performance compared to what, and doing what?

More less what I said above: "7zip benchmark using a 8MB dictionary and allocating 125MB out of the 256. Media Center, media player, device manager, computer properties and mahjong are also loaded". Please see the screenshot.
Compared to giving it more less 800MB, using hardware assisted virtualization.
Note though that when 256 stops being enough for holding the absolute minimum working set, 7zip drops to a few KB/s, because the system uses all the CPU for trashing. The thing is, the host is not affected by that, because all swapping that would hit disk, is properly cached. This is the great advantage IMO. I guess I really only need to give *enough* memory.

Right, but 7zip benchmarking shouldn't be impacted by not-enough-memory unless there's so little that 7zip literally can't load. As long as 7zip can load itself into memory, I wouldn't expect to see a performance difference between it using 256MB and it using 2048MB. In other words, it's not a good test.

A better test is how long it takes to flip between a currently running movie (that doesn't skip) in media player, plus a 7zip task, plus a few other currently running applications. Just starting an app and putting it in the background is meaningless because it will immediately be paged out, and won't impact things one way or another.

 

[turrican2097]

Originally posted by: dclive
Right, but 7zip benchmarking shouldn't be impacted by not-enough-memory unless there's so little that 7zip literally can't load. As long as 7zip can load itself into memory, I wouldn't expect to see a performance difference between it using 256MB and it using 2048MB. In other words, it's not a good test.

I see, thanks.

A better test is how long it takes to flip between a currently running movie (that doesn't skip) in media player, plus a 7zip task, plus a few other currently running applications. Just starting an app and putting it in the background is meaningless because it will immediately be paged out, and won't impact things one way or another.

But afaik it will still need to use the 125MB, it keeps needing that working set. I noticed that it has very poor performance at the very beginning, and it takes a few seconds to speed up. I assume that Vista is swapping everything else. But when I switched to the game, it was quick because there is not disk seek between paging out something else, and paging in the game data, and loading more libraries (maybe).

Note, this is somewhat unexpected, I really have more questions than answers.

I will look carefully at what process explorer tells me.

 

[Nothinman]

Yes It's strange due to the claimed requirements that I see everywhere on the net

Well most people tend to exaggerate things and most people do more multitasking in an OS directly on their machine than one in a VM. MS lists the base requirement for Vista Home at like 512M I think so I wouldn't think that 256M would be too bad although there would be a decent amount of paging.

But afaik it will still need to use the 125MB, it keeps needing that working set. I noticed that it has very poor performance at the very beginning, and it takes a few seconds to speed up. I assume that Vista is swapping everything else. But when I switched to the game, it was quick because there is not disk seek between paging out something else, and paging in the game data, and loading more libraries (maybe).

Just about everything in memory is a candidate for eviction in Windows so as long as the page hasn't been touched in a while it can be freely discarded with no I/O cost but if the page has been modified it'll have to be saved to the pagefile first. But either way everything in the background can be evicted while your 7zip benchmark runs. Switching to the game would force it to be paged back in but since you said you had the whole VPC workingset locked into memory that would happen pretty quickly.

 

[Brazen]

It's irrelevant what you (Brazen), not the forum was supposed to do. I posted in good faith, do not intend to gain anything from it, and it is reproducible. I didn't expect personal posts so soon.
You are a very important poster as you are Diamond Member. That does NOT mean that I am wrong. Which btw is irrelevant because I do not care about advocating this.

Not really sure what you are talking about here, but then I didn't really know what you were talking about in the previous post I replied to either. I never said you were wrong about anything, and I don't think anyone else did either. But I think this is all beside the point...

To the topic on hand, I suspect why you are seeing ok performance in the virtual machine because the virtual machine's page file is actually being cached in memory on the physical pc. So even though your virtual machine only has 256mb of RAM dedicated to it, it is actually using up much more than that by way of the cached page file. If you pulled all but 256mb of RAM out of your computer and installed Vista on the physical computer, I would bet that your results would be much much different.

(also: I pretty much consider post count to be irrelevant, I like to think I'm important because I give good and helpful advice 😀 realizing my previous two posts in here were more just moving-the-conversation-along posts :evil🙂