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[NW_Kohaku]

There are much more important aspects to your RAM than just what amount of RAM you have.  RAM latency is a core component of DF playspeed, since DF will need to access amounts of memory that simply can't be held in Cache (although getting as large a cache size as possible will help). 

Fortunately, if you haven't actually bought your parts yet, RAM is very cheap to upgrade to much faster kinds of RAM.

Spoiler: From the "most common myths about DF performance" thread... (click to show/hide)

Well, Wikipedia on your RAM's CAS Latency.

Very fast RAM can be pretty cheap, provided you aren't buying too much of it at once.  You can buy up to 32 or even 64 gigs of RAM, but you're going to be pretty hard-pressed to find an actual use for that much RAM, even among 64-bit programs. 

If you don't already know, spare RAM does nothing.  RAM is just storage capacity, and having excess RAM storage capacity is like paying for a whole warehouse even though you only are storing enough stuff in it to fill a small room.  That doesn't mean that if you're building your computer to last for 8 years or something that you might not find a reason to fill it eventually, but just for the record, RAM tends to get cheaper all the time, and DDR4 is going to come out in about three more years. 

Basically, to compare RAM latency, you have to look up it's general clock speed (measured in megahertz, which for those illiterate in tech speak, means "it can do things a million times per second") and then its CAS latency, measured in clocks (which is how many clock cycles the RAM can't do anything waiting for the signal to travel from the CPU to the RAM).  Start with 1,000 nanoseconds, divide by the RAM's speed in megahertz, and then multiply by your CAS latency, and you have the amount of time a theoretical bit of data will take to be fetched out of RAM and into the cache.

For example, the products on this page are all only 8 gigs of RAM, which isn't all that much nowadays, but they'd have a response time of around 5 nanoseconds on a memory fetch.  Plus they're all under $100. 

Meanwhile, this monster is going to respond at the same rate at 32 gigs of RAM, but has a price around $650 or $700. 

And here we have 4 gigs of RAM at a theoretical fetch time of 3 nanoseconds for $140.

[Kyre]

Anyone else hope that the next major release will support multithreading?

[xeniorn]

I really hope it doesn't, since that would mean the next major release would be a few years from now or so ... With nothing added to the game except better FPS scaling with modern processors and probably a million bugs. Rewriting the whole code so it can use parallel processing is a daunting task.

We can actually be quite sure it won't be so, since Toady always states his short and medium-term plans in the dev log.

Would be nice if DF could just magically begin supporting multithreading, though.

[Thief^]

Uh, no, he didn't. DF is 32-bit and is therefore restricted to 2GB of ram. There are various 3rd-party tools that will mark the DF executable as "large address aware" which allows it to use up to 4GB of ram when run on a 64-bit windows, but no more than that.

Uh... are you aware that even 32bit system can access more than 4GB RAM due to PAE? Windows 7 support PAE, and I think it was patched into XP too.

http://en.wikipedia.org/wiki/Physical_Address_Extension

PAE is the CPU feature that allows a 32-bit OS to use more than 4GB of physical address space (among other features). It doesn't do anything for applications.
It's supported by Windows XP onwards, however it's not used for >4GB ram access due to needing the support of every driver you have installed, and it wasn't a requirement for drivers of the desktop editions of Windows, so most of them don't support it (it is for the server versions, so 32-bit windows server DOES use PAE for accessing extra ram). Instead XP onwards enable PAE to be able to no-execute protect ram.

Applications can be coded to use AWE (http://msdn.microsoft.com/en-us/library/windows/desktop/aa366527(v=vs.85).aspx) which is independent of PAE, but it requires some special privileges set up for the user, so in practice no-one uses it. DF definitely doesn't use it.

[Trickman]

get the thingy that lets you shut down processors and overclock others, because that will help with DF.

... And buy a PHAT cooling system or enjoy your computer for the next 6 months, because that's what it will last until it starts smelling funny.

DF will NEVER support multithreading. Those who've tried changing a mono-thread program into multi will know what I mean. It's not a nightmare, it's worse (and the one I personally had to modify was about 1/10 of what DF is).

Let's hope processors will keep getting bigger and better caches, instruction sets and segmentation methods; since getting the clock speed up individually is out of the question (since you'd need to put your CPU in the fridge to prevent it from melting, basically).

[Putnam]

Anyone else hope that the next major release will support multithreading?

It's less "hope" and more "dream", considering just how difficult multithreading actually is.

Plus, I'm 90% sure that Toady has no experience in multi-threaded programming, which means that... well, it's not any time soon