At the MicroProcessor Forum, Dr. Brad McCredie of IBM continued to tease out particulars regarding the POWER6. The presentation discussed a lot of general microarchitecture features, but did not reveal many specific details; a full revelation of the microarchitecture will likely have to wait till ISSCC, next February. However, from the details that were revealed, it is clear that the POWER6 inherited many characteristics from its predecessors, yet made substantial improvements in others.
To view parent comment, click here.
To read all comments associated with this story, please click here.
Member since:2005-06-30
Member since:2005-07-06
And? What's your point?
It's true that x86 won the desktop and server CPU war, but it still doesn't make it a more eleguant ISA: it's still crap.
To make an analogy, you can make *any* object fly with engines powerful enough, but that doesn't make it eleguant as beautifully designed planes.
Member since:2005-07-10
It is a more efficient design. PowerPC powers a significant number of embedded devices (games consoles being a biggy). Which, if I might say, work a lot more reliably than the average PC these days it seems. IBM handles the high end with Power 5 and Power 6. Freescale (nee Motorola Semiconductor) handles the embedded market. Just since PowerPC doesn't keep up with the Joneses (ie, AMD and Intel) doesn't mean it's a bad chip, it just means more astute people use it for what they need it to do.
Member since:2005-07-06
Member since:
2005-07-10
You can actually run code from PPC to x86 or vice versa using advanced binary translation, dynamic recompilation or emulation. You get a 4x speed slowdown on average with dynamic recompilation, that would be less if the code was recompiled with binary translation. In fact, in some tests, binary translating from x86 to x86 for hotpaths and some simple optimisations gives a modest speed increase (maybe 5-25%) say in the Dynamo-RIO system.
Basically, x86 is garbage. It hangs around like a bad smell to cause misery to programmers and holds people back from real improvements. It's a wonder Intel keeps up, basically their CPU's are RISC-like underneath with a shockingly bad x86 architecture thrown on top. I'd imagine if a better, more reliable architecture turned up that everyone suddenly jumped onto Intel could probably rewrite the microcode to run it in a matter of weeks on their existing chips if they wanted to support it (and it was supported).
The main issue with legacy code isn't the architecture - it's the API calls and OS calls that make it a problem. Look at Wine - taken years to rewrite most of the Windows APIs. Executor got a good chunk of the way on the MacOS API's. GNUStep a good effort at OpenStep.
The fact is the different OSes refuse to play ball with each other API or driver wise. EFI -may- resolve some of the low level hardware problems, but as other people (like Linus et al) are saying, it's too hard as it reminds them of something they didn't like (a long long time ago... maybe in a distant galaxy far far away).
Guys like SciTech Solutions (http://www.scitechsoft.com/products/dev/sdk_home.html) are doing a pretty good job of cross-platform drivers (notably video and audio). If a small company can get the job done, just think what Microsoft, Apple and GNU/Linux developers could do with the right incentives.