6 ms·

This makes me wonder when 128 bit processing will come around.

wmf 13y ago
As soon as you can put 2^64 bytes of RAM in a PC, I guess.
codeflo 13y ago
We already have 128-bit registers for vector computations (for example, the SSE registers in x86). As for addressing 128 bits of memory: that's more than a century off even if memory continues to double every two years (which doesn't seem likely to begin with). It's actually plausible that the step to 64-bit addressing was the last one, ever.
- dragontamer 13y ago
  64-bit ARM means passing around 64-bit pointers by default. In most code settings, this pollutes the cache (you can only hold half as many pointers), and leads to slightly weaker performance. 64-bit computing is NOT an advantage in the phone world. It is a massive advantage for database applications or large web services... but certainly not for phone apps in the near future.
  - codeflo 13y ago
    I know what 64-bit computing is. And I didn't say anything about phone chips, or ARM. It seems like you're posting this rant to every subthread, regardless of content?
- data-cat 13y ago
  That is an interesting conclusion. I did not realize x86 already had 128 bit registers. That was really what I was referring to. We might not need to worry about addressing more memory yet but I feel like larger registers will still be useful.
  - stephencanon 13y ago
    Actually, x86 already has 256-bit vector registers (AVX), and will have 512-bit vector registers in a few years (AVX-512). If you include the exotic-but-still-x86-based xeon phi it already has 512-bit vector registers.
- colanderman 13y ago
  Don't know why you were downvoted. Modern x86 chips not only have 128-bit vector registers, but also 256-bit ones: http://en.wikipedia.org/wiki/Advanced_Vector_Extensions http://en.wikipedia.org/wiki/Advanced_Vector_Extensions (And while one could argue that a vector register isn't a "real" general-purpose register, the primary difference is that you can't perform fullwidth arithmetic, which is of very little use > 64 bits anyway.)
dragontamer 13y ago
Your comment made me lol. +1, easily. No seriously, there is little to no speed difference in 32-bit vs 64-bit computing. The REAL benefit is the ability to address memory beyond 4GBs. But even the most high-end phones are stuck with 2GB... hell, a number of laptops are still shipping with 2GB of RAM. Let alone phones. The 64-bit "advantage" is almost entirely a marketing gimmick. That said, it is a known fact that Apple's iPhone chip is leagues ahead of its competitors in terms of performance / watt. Qualcomm has a value buy with Snapdragon and their integrated LTE chip + FCC conformance. But Apple has full integration, and controls the software / hardware from bottom up. That is a real advantage that is leading to improved battery lives and faster performance. (This is less an "Apple Advantage" and more of an "Android disadvantage". Android should be able to catch up if they got their act together... but the reliance on Dalvik-VM code and unoptimized APIs leads to noticeably worse battery life) Beyond that, Apple is beginning to invest into state-of-the-art foundries, possibly to create chips in house by the year 2016 or 2017. They've also bought out the high-end 20nm wafers through 2014, forcing their competitors to lag behind on the older 28nm process nodes. (Hell, even AMD / NVidia are feeling the sting. All AMD / NVidia roadmaps to better GPUs are at 28nm technology... Only Intel: who has reached 14nm on their in-house labs, remains unaffected by Apple's purchasing power) When your company has $100 Billion in cash, you can afford to have a process node advantage over your opponents.
- wsc981 13y ago
  > "Beyond that, Apple is beginning to invest into state-of-the-art foundries, possibly to create chips in house by the year 2016 or 2017. They've also bought out the high-end 20nm wafers through 2014, forcing their competitors to lag behind on the older 28nm process nodes. (Hell, even AMD / NVidia are feeling the sting. All AMD / NVidia roadmaps to better GPUs are at 28nm technology... Only Intel: who has reached 14nm on their in-house labs, remains unaffected by Apple's purchasing power)" Very interesting. Would you have a source? I know Apple did the same "trick" with touch screens when the iPhone was introduced. I think these actions are typical of Cook - from what I understand he was earlier (before he became CEO) responsible for the whole inventory chain management and it's likely an area he's still involved in.
  - 13y ago
nradov 13y ago
IBM System i (AS/400) servers have supported 128 bit pointers for decades.
- colanderman 13y ago
  Nice. I suppose this is for memory-mapped file I/O? Or do those beasts really have access to terabytes of core? (In which case I will become jealous of my dad, who works with AS/400s.)
  - nradov 13y ago
    The former. They don't support any more physical memory than other high-end servers.

wmf 13y ago

As soon as you can put 2^64 bytes of RAM in a PC, I guess.

We already have 128-bit registers for vector computations (for example, the SSE registers in x86). As for addressing 128 bits of memory: that's more than a century off even if memory continues to double every two years (which doesn't seem likely to begin with). It's actually plausible that the step to 64-bit addressing was the last one, ever.

dragontamer 13y ago
64-bit ARM means passing around 64-bit pointers by default. In most code settings, this pollutes the cache (you can only hold half as many pointers), and leads to slightly weaker performance. 64-bit computing is NOT an advantage in the phone world. It is a massive advantage for database applications or large web services... but certainly not for phone apps in the near future.
- codeflo 13y ago
  I know what 64-bit computing is. And I didn't say anything about phone chips, or ARM. It seems like you're posting this rant to every subthread, regardless of content?
data-cat 13y ago
That is an interesting conclusion. I did not realize x86 already had 128 bit registers. That was really what I was referring to. We might not need to worry about addressing more memory yet but I feel like larger registers will still be useful.
- stephencanon 13y ago
  Actually, x86 already has 256-bit vector registers (AVX), and will have 512-bit vector registers in a few years (AVX-512). If you include the exotic-but-still-x86-based xeon phi it already has 512-bit vector registers.
colanderman 13y ago
Don't know why you were downvoted. Modern x86 chips not only have 128-bit vector registers, but also 256-bit ones: http://en.wikipedia.org/wiki/Advanced_Vector_Extensions http://en.wikipedia.org/wiki/Advanced_Vector_Extensions (And while one could argue that a vector register isn't a "real" general-purpose register, the primary difference is that you can't perform fullwidth arithmetic, which is of very little use > 64 bits anyway.)

dragontamer 13y ago

Your comment made me lol. +1, easily. No seriously, there is little to no speed difference in 32-bit vs 64-bit computing. The REAL benefit is the ability to address memory beyond 4GBs. But even the most high-end phones are stuck with 2GB... hell, a number of laptops are still shipping with 2GB of RAM. Let alone phones. The 64-bit "advantage" is almost entirely a marketing gimmick. That said, it is a known fact that Apple's iPhone chip is leagues ahead of its competitors in terms of performance / watt. Qualcomm has a value buy with Snapdragon and their integrated LTE chip + FCC conformance. But Apple has full integration, and controls the software / hardware from bottom up. That is a real advantage that is leading to improved battery lives and faster performance. (This is less an "Apple Advantage" and more of an "Android disadvantage". Android should be able to catch up if they got their act together... but the reliance on Dalvik-VM code and unoptimized APIs leads to noticeably worse battery life) Beyond that, Apple is beginning to invest into state-of-the-art foundries, possibly to create chips in house by the year 2016 or 2017. They've also bought out the high-end 20nm wafers through 2014, forcing their competitors to lag behind on the older 28nm process nodes. (Hell, even AMD / NVidia are feeling the sting. All AMD / NVidia roadmaps to better GPUs are at 28nm technology... Only Intel: who has reached 14nm on their in-house labs, remains unaffected by Apple's purchasing power) When your company has $100 Billion in cash, you can afford to have a process node advantage over your opponents.

wsc981 13y ago
> "Beyond that, Apple is beginning to invest into state-of-the-art foundries, possibly to create chips in house by the year 2016 or 2017. They've also bought out the high-end 20nm wafers through 2014, forcing their competitors to lag behind on the older 28nm process nodes. (Hell, even AMD / NVidia are feeling the sting. All AMD / NVidia roadmaps to better GPUs are at 28nm technology... Only Intel: who has reached 14nm on their in-house labs, remains unaffected by Apple's purchasing power)" Very interesting. Would you have a source? I know Apple did the same "trick" with touch screens when the iPhone was introduced. I think these actions are typical of Cook - from what I understand he was earlier (before he became CEO) responsible for the whole inventory chain management and it's likely an area he's still involved in.
- 13y ago

nradov 13y ago

IBM System i (AS/400) servers have supported 128 bit pointers for decades.

colanderman 13y ago
Nice. I suppose this is for memory-mapped file I/O? Or do those beasts really have access to terabytes of core? (In which case I will become jealous of my dad, who works with AS/400s.)
- nradov 13y ago
  The former. They don't support any more physical memory than other high-end servers.