RAM: 2gigs(32-bit) vs 4gigs(64-bit)!!

Ok. Lately i've been wondoring (for no reason at all )....
-Is a 2-gig ram to a 32 bit OS what a 4-gig is to a 64 bit OS? Will a 64-bit application (in a 64-bit OS) require twice as much ram as a similar 32-bit application (in a 32-bit OS)?????
-Which is better or faster, 4 gigs on a 32-bit OS or 2 gigs in a 64-bit OS

 

No. 64bit apps require no more ram than 32bit apps. In fact, in some applications designed for a 64bit environment, can function more efficiently.

 

I hate to argue with you, but i will slightly. They dont always require more, alot of times will require slightly more, I am pretty sure 32 bit variables are padded in 64 bit apps? One thing you will notice straight out is Vista x64 uses quite a bit more ram then 32 bit.

As I can not currently compile for windows in 64 bit I havent tested any difference in my applications. Since the pentium 1 we have been able to take advantage of 64 bit variables due tot he 64 bit data bus and registers but the 32 bit address bus and instruction set kept us with 32 bit software. I think this is why most programs wont see a huge change in ram usage when recompiled for 64 bit.

In my opinion lets say your running your nearly max of 3GB in a 32 bit OS, you will survive but be more comfortable with 4GB in 64 bit. Not a huge amount needed over 32 bit.

 

I find 64bit Windows better at some things: for example, multi tasking seems to work much better than on 32bit Windows (multi tasking == running many applications at once). By better I mean faster and less HDD activity.

Referring to the initial question, if there are only 64 bit processes in the 64 bit Windows: that is nowadays (almost) completely impossible. Even when you install Vista 64bit, when you launch IE it will start a 32 bit IE (although you can start 64 bit IE if you want to), but every other browser (to the best of my knowledge) is 32 bits. Windows Media Player, Winamp and many other programs are only available in 32bits (and Vista 64 includes many others), so you cannot really run only 64bit programs in a 64bit Windows today

But that is no problem, 32bit and 64bit applications run along fine in 64bit.

 

The *main* plus point for a 64-bit OS for meh personalleh is that it is able to see/utilize more than 3.2 GB RAM. It pissed me off that I had 4 GB RAM and 800 MB of it was not being used by Vista 32 bit, so I made teh switch to teh 64-bit world with not one problem........


Running Win 7 Ultimate 64 BIT FTW

Win7 pwnts j00

 

32bit processes can sometimes double up and run twice as fast if you use 64bit OS.

 

Is this true? I haven't heard this before. Honestly asking, not challenging.

 

Serious ?
I have also not heard this before...

 

by itself, going from 32bit to 64bit allows one thing: more memory to access.

from 4gb to 4billion times 4gb.

BUT in our computer land, it means as well the shift from x86++ to x64 code. and this means two things:

first: all memory pointers grow to twice their size. from 32bit to 64bit. so all memory pointers in an application use 2x as much memory. this does not affect the rest of the code AT ALL, only memory pointers. that means an app would only grow to 2x the size if all it would be is memory pointers (and no code => no app really at all).

second: x64 has some optimisations that could never happen really on x86 land, because it was an old, frozen standard of, what, 15 years? 20 years? ago. with x64, the whole instruction standard had to be rewritten anyways to support 64bit adresses => they tweaked the standard a bit. so in 64bit mode, we have some new additional registers, means more data in the fastest "cache" in the processor, some new default instructions, and that, all in all, can create faster applications. but not 2x as fast. but a bit fast. sometimes 20% faster got reported.

so the result: 64bit apps get a bit bigger, a bit faster. but not by much in both cases.


the verdict:

if you have now 3.5gb ram accessible in 32bit windows and move to 64bit to have 4gb, your a-bit-bigger-apps just use that bit-more-ram, resulting in the end in about the same usage. => not really needed or useful in the general case.

but: apps can be a bit faster, the os can be a bit faster (the os, again, can forget some legacy-stuff from 32bit or 16bit days), so you still may gain from 64bit vista/win7, even while you don't gain much in ram.

 

6GB RAM!

 

triple channel! I'm sure you'll see that more and more on desktops with i7 gaining favor, and of course eventually notebooks. Of course cramming three DIMMS in a laptop could be challenging.

 

Only DDR2, but still, 6GB!

 

This isn't true. It applies (depending on compiler, and then on data dependencies and potential pipeline hazards) to EPIC architectures, which is how the Itanium is built.

 

Hate to hit you like everyone else, but I have benched 32 bit applications Under Vista x64 and they ran 99.9% the same on xp. 64 bit applications on a 64 bit os/cpu will run faster than a 32 bit application (though arguably dependent on what its actually doing).

Good bench to show is Cinibench 32 bit versus 64 bit. Also as the applications are run in a virtualized environment of sorts ram usage shouldnt increase unless padding is necessary and then it would still be minimal.

 

I said sometimes... Most of time the processes doesn't double up, at least that's what I've read somewhere few years ago.

 

Someone is trying to expand the fact that memory pointers are twice as big in x64 systems to x64 programs use twice as much memory.

Sigh.

Your memory usage in general will be the same. Because most of the programs you run in x64 Vista are still technically 32 bit programs. The OS just accommodates for them.

 

Wouldn't that be a little bit like saying that my house must have gotten bigger (or the distance between houses got bigger) since the US Post Office went from the standard 5-digit zip-code to the much-maligned 5+4 zip-code?

 

No not really, more like saying standard envelop sizes will require 80% more width to fit the address.

 

Really? Let's see, the original point was that there were some saying that a 64-bit pointer to a memory location would, ipso facto, mean that more memory was being used at the location pointed to. That, clearly, is not true. However, it is true that it takes more memory space to actually store the value of that 64-bit pointer than it would take to store the value of a 32-bit pointer - 8 x 8-bit bytes versus 4 x 8-bit bytes.

So, by analogy, it is clearly the case that, in moving to 5+4 from the old 5-digit zipcodes, the Post Office forced everyone to spend a bit more surface area on their envelopes writing down (that is, storing) the 5+4 zipcode; however, it would be false to say that, just because the zipcode - the pointer to a particular house - got bigger, that some characteristic of the house itself also, ipso facto, got bigger, which is the point Surfasb was critiquing.

 

I should add something of interest here.

If not properly rewritten for 64 bit, lets just say we got lucky and the new 64 bit compiler (I am still waiting 6 months for myne....) managed to compile with almost no changes (application that doesnt interface with drivers etc etc).

When declaring a normal variable (not manually using pointers) say an Integer, under the 32 bit compiler I declare Integer rather than Int32 and this is being used for something that doesnt require a value over 2.1x billion(not gonna remember or look it up) so I am not declaring Int64 or the equivalent. Some compilers default some variables to the default (address width?.....) and Integer on a 32 bit compiler will be 32 bits in length and on the 64 bit compiler might default to 64 bit.

In this transition without proper rewriting applications might allocate ram unecessarilly. I only bring this up because under my last transition Strings became 2 bit per char default as well as Char/Pointer Char and anything else related to unicode. I could see the same thing happening with 32 bit default variables going to 64 bit.... might not u never know with the company at the wheel.

That of course is all up to lazy programmers, someone using pointers is either gonna run into in issue due to compiler changes or have had properly written code to begin with and it will not have this issue, you manually allocate memory anyways.

 

Two 32-bit processes cannot be executed by the same execution unit on the CPU. If an execution unit is operating on a 16-bit instruction, it is 100% utilized. If it is operating on a 64-bit instruction, it is also 100% utilized.

 

he was talking about RAM usage, not processor usage.

and jackluo, just check my lengthy post, it explains why apps can never double up. it's the theoretical limit only reachable in the case where the app is no app at all

 

For regular use 2gb on x32 or 4gb on x64 you won't see that much speed difference since Vista is also accessing your HDD for pagefiles and what nots. For extensive graphics and multimedia manipulation with a dedicated 64bit program then you will see a difference. You will see more speed with a quad core CPU with 4gb or more RAM using 64bits. You also have to factor in the speed of RAM and your motheboard's FSB speed.

 

Shyster is correct in his analogy. My post is a bit simplified though. Technically, it's more than memory pointers. But we've rammed the message home.

Your x64 program's memory usage will vary.

 

The original statement made was about the speed at which a 32-bit process can execute under a 64-bit operating system.

 

Danke.

....​

 

haha okay, now i see