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Apple "has stuff to blow away intel"
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Well I can't speak for madamimadam though I seem to have been doing so. The Gates quote does specifically say processors not memmory.
Well, I don't see the point in jumping into an arguement that is looking like it would just get totally childish but thanks MacBandit.
All I am going to say is that it is not possible to find an example of use for 128-bit because, as my point suggested, it would not be now that they would be used but in years to come.
Asking me to give an example of how to use 128-bit chips is as good as asking someone the use for 64-bit chips when 32-bit chips first came out.
Obviously, people would not know what to do with a 64-bit chip when the 32-bit chips came out because apperently "a number of things can be handled by integers as small as 8 bits, a whole lot more can be handled by 16 bits, and" "everything can be done in 32 bits".
ddtlm, calm the **** down and have a baby... I am told they make everything worthwhile.
- For Chuck -
All I am going to say is that it is not possible to find an example of use for 128-bit because, as my point suggested, it would not be now that they would be used but in years to come.
Asking me to give an example of how to use 128-bit chips is as good as asking someone the use for 64-bit chips when 32-bit chips first came out.
Obviously, people would not know what to do with a 64-bit chip when the 32-bit chips came out because apperently "a number of things can be handled by integers as small as 8 bits, a whole lot more can be handled by 16 bits, and" "everything can be done in 32 bits".
ddtlm, calm the **** down and have a baby... I am told they make everything worthwhile.
- For Chuck -MacBandit:
madamimadam:
I would be interested to know what exactly this quote is, since I've never heard of it before.
madamimadam:
Now we're just back to the hand-wavy arguements again, about compelling, inevitable uses for 128 bits that we just can't possibly imagine. Speaking as someone who puts integers to work every day in programs I write, it seems very obvious to me that the uses for native 128 support are quite few and far between (addressability being the best use), but I'm not sure how I am going to be able to convince you of the same thing.
I don't see how you can conclude that no one could imagine a use for 64-bitness simply because most things are handled best by fewer bits.
In the late eighties I worked on a project developing a computer arranged in a ring with 16 slots per ring and a word size of 512 bits. This little gem cranked out answers every 5ns. The problem then was not finding a use but finding a compiler design that could keep it busy.
One day I talked to a weather bureau guy about getting more sensors. He said that with the computers and sensors they had then that the computer models were 5 hours behind the real weather and that adding more sensors would compound the problem rather aid in a solution.
What about calculating the value of money around the world so money can be moved from currency to currency? Maybe 128 bits is not nearly enough. Depends on how many different operation can be contained in a word wouldn't you think?
64-bits..
why is everyone missing the big reason to go 64-bit? it's memory -- 32-bit systems can only address 4gigs of memory space without using a bank-swapping technique. Sure, it wouldn't be too hard for Apple (or Microsoft, for that matter) to support machines with more than 4gigs of RAM, but individual processes couldn't access more than 4gigs at once.
Going to 64-bit will mean that processes will be able to use files bigger than 4gigs and allocate more than 4gigs of memory. This is not only good for databases, but also video editing applications as well. Also, with the way OS X uses memory for things like the Window server, the extra memory space will help.
Also, another thing to consider -- all of the PowerPC chips already have a 64-bit data bus. The G4 extends it to 128-bit for Altivec. All the move to 64-bits means is that Integer instructions will be able to use 64-bits as well. If a program only uses 32-bit instructions, its not going to causes a slowdown -- it will be just as fast as it currently is. The instruction size isn't changing to 64-bits, so there isn't an automatic doubling of memory bandwidth required.
Just think of the 64-bit powerpc as an extension -- one that's been planned from the beginning. The registers will be bigger -- including the program counter. There will be some new instructions to support 64-bit integer math (not very useful unless you need numbers bigger than +/- 2 billion (or 4 billion if you don't care about negative numbers).
When the 970 comes out (if it does show up in an Apple product), Apple will just need to change Darwin to support the larger address space, the code in the scheduler to save the registers (64-bit now -- need more space), and any code that deals with allocating or mapping in memory. Most likely, they will go the route that Sun took with Solaris -- they will add some new routines that deal with 64-bit pointers, and maybe some glue routines that translate between the two. Code will have to be explicitly compiled for 64-bit mode, and most programs will continue to be compiled as 32-bit only.
The bigger deal for the 970 is the increased overall speed of the processor and the added memory bandwidth. 64-bit is just a minor addition in the big picture -- one that is needed, but it's not earth-shattering like the move from 16-bit to 32-bit (or, for the Mac, 24-bit to 32-bit )
why is everyone missing the big reason to go 64-bit? it's memory -- 32-bit systems can only address 4gigs of memory space without using a bank-swapping technique. Sure, it wouldn't be too hard for Apple (or Microsoft, for that matter) to support machines with more than 4gigs of RAM, but individual processes couldn't access more than 4gigs at once.
Going to 64-bit will mean that processes will be able to use files bigger than 4gigs and allocate more than 4gigs of memory. This is not only good for databases, but also video editing applications as well. Also, with the way OS X uses memory for things like the Window server, the extra memory space will help.
Also, another thing to consider -- all of the PowerPC chips already have a 64-bit data bus. The G4 extends it to 128-bit for Altivec. All the move to 64-bits means is that Integer instructions will be able to use 64-bits as well. If a program only uses 32-bit instructions, its not going to causes a slowdown -- it will be just as fast as it currently is. The instruction size isn't changing to 64-bits, so there isn't an automatic doubling of memory bandwidth required.
Just think of the 64-bit powerpc as an extension -- one that's been planned from the beginning. The registers will be bigger -- including the program counter. There will be some new instructions to support 64-bit integer math (not very useful unless you need numbers bigger than +/- 2 billion (or 4 billion if you don't care about negative numbers).
When the 970 comes out (if it does show up in an Apple product), Apple will just need to change Darwin to support the larger address space, the code in the scheduler to save the registers (64-bit now -- need more space), and any code that deals with allocating or mapping in memory. Most likely, they will go the route that Sun took with Solaris -- they will add some new routines that deal with 64-bit pointers, and maybe some glue routines that translate between the two. Code will have to be explicitly compiled for 64-bit mode, and most programs will continue to be compiled as 32-bit only.
The bigger deal for the 970 is the increased overall speed of the processor and the added memory bandwidth. 64-bit is just a minor addition in the big picture -- one that is needed, but it's not earth-shattering like the move from 16-bit to 32-bit (or, for the Mac, 24-bit to 32-bit
)Do we have any engineers in here? I have yet to read a sensible post regarding bit sizes.
In the most general sense going from 32 bits to 64 bits will NOT increase the speed of the system. What it DOES allow you to do is move data around much more efficiently. Currently, most, if not all, 32 bit processors deal with 64 bit registers. Remember too, that these are INTERNAL buses and have nothing to do with accessing/addressing external memory...
The 7457 (G4) has a 36 bit address bus and a 64 bit external data bus (the PPC970 has a 42 bit address bus). There are 32 64 bit Floating Point Registers and there are 128 bit internal buses. The reason why it's considered a 32 bit chip is because the Integer Units are only 32 bits wide. So, data is flying around in there much more efficiently than the IUs can handle it. There are 3 main Integer Units, which means it can parallel task 3x32 bit instructions per clock cycle.
In "normal" operations this is enough. But, when you deal with multimedia (video, audio) and/or extremely accurate floating point precision (scientific) you'd be more efficient moving 64 bits than 32. Take a look at the newer video accelerators, they have 64 bit and even 128 bit pipelines and FPUs.
If all you do is "surf the net", play Solitaire and read email 64 bits is going to do NOTHING for you. If, OTOH, you do video editing, sound recording/processing, real time weather modeling, micro-precision CAD drawings or wind tunnel modeling 64 bits is going to give you A LOT...
Plus, pushing 64 bits instead of 32 bits is more efficient, hence lower operating temperatures and less power...
In the most general sense going from 32 bits to 64 bits will NOT increase the speed of the system. What it DOES allow you to do is move data around much more efficiently. Currently, most, if not all, 32 bit processors deal with 64 bit registers. Remember too, that these are INTERNAL buses and have nothing to do with accessing/addressing external memory...
The 7457 (G4) has a 36 bit address bus and a 64 bit external data bus (the PPC970 has a 42 bit address bus). There are 32 64 bit Floating Point Registers and there are 128 bit internal buses. The reason why it's considered a 32 bit chip is because the Integer Units are only 32 bits wide. So, data is flying around in there much more efficiently than the IUs can handle it. There are 3 main Integer Units, which means it can parallel task 3x32 bit instructions per clock cycle.
In "normal" operations this is enough. But, when you deal with multimedia (video, audio) and/or extremely accurate floating point precision (scientific) you'd be more efficient moving 64 bits than 32. Take a look at the newer video accelerators, they have 64 bit and even 128 bit pipelines and FPUs.
If all you do is "surf the net", play Solitaire and read email 64 bits is going to do NOTHING for you. If, OTOH, you do video editing, sound recording/processing, real time weather modeling, micro-precision CAD drawings or wind tunnel modeling 64 bits is going to give you A LOT...
Plus, pushing 64 bits instead of 32 bits is more efficient, hence lower operating temperatures and less power...
Mirus:
I do so love it when people start off that way.
Some busses are even wider, for example the L2->L1 data bus is claimed to be 256 bits wide in Motos 7455 docs.
Well double-precision (64-bit) floating point has been supported by 32-bit CPUs for some time, so I don't quite see where you are going with that.
How do 64-bit integers help any of this?
Only in the case that all 64 bits are actually being put to use, which would not be the common case.