AMD Says Power Efficiency Still Key
Larsonist writes to tell us that even though AMD's new architecture wont be released until mid-2007 they are still letting people in on what some of the new features will be. From the article: "While clock speeds have not been revealed, each of the four cores will integrate 64 KB L1 Cache and 512 KB L2 cache. The native quad-core architecture will also include a 2 MB shared L3 cache, which may increase in capacity over time. The processor will have a total of four Hypertransport links - up from three today - that provide a total bandwidth to outside devices of 5.2 GB/s. AMD is also thinking about integrating support for FB-DIMMs 'when appropriate.'"
But will it run Vista? (j/k)
Is Vista going to support 4 cores, or like XP Pro and 2k, limit it to 2 "cpus" so they can charge more for the server version?
Tequila: It's not just for breakfast anymore!
The article is very light on details but the one picture implies power control at the core level. For example if core-1 is running a 100% workload and core-2 has a 50% workload, core-3 and core-4 can be halted resulting in a power load of only 45% the total 4-core max load.
... run OS/2?
Joking aside, lately I've been pondering AMD's next move in the everlasting Intel vs. AMD chess game.
I'm here for hoping they can pull ahead again and force Intel to do the same.
Always Remember: competition is good!
is to reduce the distance between their transistors from 90nm to 65. Intel started shipping their 65nm chips nearly a year ago (OCT 2005), while AMD has yet to ship any. AMD isn't expected to be fully converted to the 65nm process until mid-2007, and by then Intel is expected to start shipping their 45nm chips. AMD is playing catch-up these days and it's hurting them bad.
AMD now provides a TSC (cycle counter) that doesn't vary in speed when the core speed changes. This greatly helps with timekeeping.
As for race conditions: that is pretty well taken care of already. SGI has Linux on a 2048-way system now.
Well, at least if you are in a data center.
There are two huge concerns in a typical data center enviornment: Heat and Power. These two areas are key because of the density of servers today. We're cramming so much processing and storage into 48U that people 10 years ago couldnt have even dreamed of even existing. Delivering enough power to run 48 servers can be difficult if each server is pulling 4 amps each (thats 192 amps). Considering most circuits are 20 or 30amps, thats alot of circuits to fit in one rack.
This was always the biggest reason why Dell servers were not as popular with the companies that I have worked with. Quite simply, AMD was kicking Intel's ass with heat and power. I heard many people say they'd start ordering Dell servers by the pallet if they sold AMD processors (looks like they finally listened).
I'm sceptical that this technique will be very useful. (Of course, AMD is full of smart people and I'm just some net.moron.) I don't think it will be very common for the load on a 4-core processor to be somewhere the middle like 1.5. It's either going to be mostly idle (load close to 0) so you might as well power down the whole chip, or going full blast with the load as high as I think will give me the most throughput. For example, when compiling (and that's when I wish I had more cores) I'm gonna "make -j n" and my load is going to be about n, and that number is going to be chosen to be one more than the number of cores I have (or something like that). If I have a 4-core machine, do you think I'm going to make -j 2? No way.
I can't think of many situations where I would have one core running at 100% and another at 50% and the others idle, for any significant length of time. I can imagine a desktop user clicking on something and maybe for a few milliseconds that load is somewhere around that, but then the work gets done and you're idling again. Or the user asked it to do something "hard" so all cores are near 100% (except maybe while waiting for I/O) for a "long" time.
Am I wrong? What kinds of things does your computer work on, which are a little parallelizable but not very much?
As copyright owner of this comment, I authorize everyone to defeat any technological measure which limits access to it.
AMD Says Power Efficiency Still Key
I'll be happy with these new processors as long as I can still efficiently heat my apartment with them.
I got my Linux laptop at System76.