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[MitchTheLich]

So i have a relatively small amount of computer knowledge. I will soon have a 4 core computer with 16gb ram. Can i use virtualbox to create a virtual machine with like 14gb ram and then just run DF with it to make 1 more powerful computer? Or is that not how that works?

[smeeprocket]

DF isn't going to access more than 2gb, 4gb if you optimize it using a large address aware program if you have a 64 bit system.

Most games aren't going to access more than 4gb, tbh.

It's not that DF will use all your ram and then crash, it won't really use that much at all. It just can't access that much.

So this would probably do nothing, though a solid state drive would probably speed things up somewhat. I don't know how much tho.

[MitchTheLich]

It's got a decent graphics card, invidia 980 iirc, so i am hopeful about the other games. I've never heard of the large address aware thing, any more tips/info on that?

[Metalax]

It's not really memory size that is the issue with DF slowdowns, it is the core speed of the CPU that is the limiting factor in almost every case. DF is not, to my knowledge, set up to run on multiple threads and as such is limited to running on a single core of your CPU.

You can get some improvement by messing with core affinities such that DF is the only program with access to one of the cores, but otherwise there really isn't that much you can do to improve its running on your machine without upgrading your CPU to one that has a higher individual core speed.

[puke]

or move all the program files to a ram disk...

[utunnels]

VMs don't make things faster, usually. In fact, they are usually slower.

[mndfreeze]

I have an SSD in my system at home on an i7-3820 overclocked cpu (4 cores) and 16GB of ram and an nvidia 680.  Lately I've been copying my DF save to a usb stick between work and home since work is getting slow for our year end freeze. The other day I accidentally copied my game install onto my 1TB non-ssd storage disk in my home system and the drop in performance was insane.  I didn't really think DF was hitting my drive that much but with all those thousands of tiny files it apparently does quite a bit.  So for sure install it to an SSD if you have one. 

I asked in the future of the fortress thread about the possibility of it being written to support 64 bit or multithreading and didn't get a respnose from Toady, and others who chimed in basically said 'not gunna happen' since the amount of work to rewrite and update that sort of thing would be a masssssive undertaking. 

As others have said though OP, a VM won't help nor does it really work the way you were thinking anyway.

[Orange Wizard]

DF and Hardware Performance: Random Factoids:

• Dwarf Fortress is, in fact, multithreaded. However, all of the game is run on one thread. The other thread is the rendering code.
• Your graphics card has somewhere between very little to no effect of DF's performance. A few hundred letters are vastly easier to draw than hundreds of thousands of polygons.
• Because (usually) DF cannot access more than 2 Gb of RAM at any time, and (usually) doesn't use that much in the first place, the amount of RAM you have is largely irrelevant.

[Sergarr]

DF and Hardware Performance: Random Factoids:

• Dwarf Fortress is, in fact, multithreaded. However, all of the game is run on one thread. The other thread is the rendering code.
• Your graphics card has somewhere between very little to no effect of DF's performance. A few hundred letters are vastly easier to draw than hundreds of thousands of polygons.
• Because (usually) DF cannot access more than 2 Gb of RAM at any time, and (usually) doesn't use that much in the first place, the amount of RAM you have is largely irrelevant.

I take objection to the RAM point. DF uses a LOT of RAM.

[Arx]

It's running at 185MB at the moment for me. It's very likely that it's limited to 2GB if it's 32bit.

[Orange Wizard]

It does depend on the size of your worlds. If you're running larger worlds (which isn't advisable in the first place because they drag down FPS) your RAM usage will increase as well. Larger embark sites have a similar effect.

[Arx]

That would be consistent with my experience, since I almost always play 2x2 embarks in pocket worlds.

[arbarbonif]

I thought that RAM latency was considered a big point too.  So faster RAM helps alot.

[Codyo]

It's not really memory size that is the issue with DF slowdowns, it is the core speed of the CPU that is the limiting factor in almost every case. DF is not, to my knowledge, set up to run on multiple threads and as such is limited to running on a single core of your CPU.

You can get some improvement by messing with core affinities such that DF is the only program with access to one of the cores, but otherwise there really isn't that much you can do to improve its running on your machine without upgrading your CPU to one that has a higher individual core speed.

In order to limit the dwarf fortress process to one core effectively, you're going to have to switch off that affinity for every other process. At default, the core will still be used by everything else. There may be a way to do this fast and simple, but I don't know of it.

I agree a smaller embark helps a lot. The performance in a 3x3 is massively better than 4x4.
The biggest helpers for FPS are the embark size and turning off temperature and weather. Turning off temperature will change the game a bit though, you'll lose fun features like burning\freezing to death. No rain either with weather gone.

[wierd]

Dwarf fortress is a 32bit application, yes.

It is also memory-bound.
http://en.wikipedia.org/wiki/Memory_bound_function

DF uses large, structured arrays of data in memory which are many "words" in size for the elements contained in them. This means that some of DF's evaluations take multiple fetch cycles to complete. 

This can be alleviated somewhat with faster CPU, but the real deal is the speed of the memory bus. The speed of the memory bus and the speed of the CPU are not the same thing, and haven't been since at least the 80s. To help get around this problem, modern CPUs contain instruction and data caches to hold frequently accessed data or program stack information so that the CPU does not have to perform nearly as many memory fetch cycles, which can cause the CPU to sit idle for many instruction op cycles while data gets fetched from memory.

http://arstechnica.com/gadgets/2002/07/caching/

The things that will really speed up DF are:
Larger cache size
Faster memory bus speed
Faster CPU speed

In that order.