The 8641D and 8641 (single core version) are not expected to sample until 2H 2005 so they won't be turning up in machines in the immediate future but they should prove very interesting when they do. The CPU performance will increase significantly due to the inbuilt memory controllers and clock speed boost (no speeds have been quoted yet other than "at least 1.5GHz" but 1.7GHz seems to be expected) but more than this the overall system performance should increase considerably. This is in contrast to PC designs which go all out to boost CPU performance and leave the rest of the system lagging behind. The new PCI Express will give additional bandwidth but the current 11 year old PCI bus will just about handle a single Gigabit Ethernet port, never mind four!
For years embedded version of the PowerPC CPUs have been available which include all manner of connectors and functionality but the highest performance PowerPC CPUs are typically stand alone components requiring north and south bridges for interfaces. It is an interesting development that Freescale have now chosen to introduce similar integrated functionality on their highest performance CPU. However, this device is not aimed primarily at PCs so it cannot be taken as a sign that PC CPU vendors are planning on going to this level of integration in the immediate future. While users measure systems by pure CPU benchmarks they'll get systems which are designed to perform well in pure CPU benchmarks, even if you actually use the complete system.
Servers may not seem an obvious target for a G4 based CPU but these are the perfect target for a CPU which optimises system performance over raw CPU performance, servers after all, are doing many things at once so a 8641D could perform surprisingly well. High network throughput requires a lot of computing power, the TCP/IP hardware assist will help with this leaving the CPU to work on the actual content to be served. Low latency connections mean that data can be moved around and accessed for processing quickly.
The low power consumption is also a factor to be considered if a large number of servers are in use, high power consumption CPUs produce heat which has to be removed, usually by cooling systems which cost considerably more than the computer hardware. CPUs with low power consumption can be cooled easier and cheaper and having the north-bridge integrated on the CPU saves even more power.
Operating Systems
It's a pity something like this wasn't around when BeOS was still about, it was designed for multiprocessor systems from the get go so would have ran like a dream on such a CPU, hopefully Haiku and Zeta will be able to pick up the benefits though. Of course there are many multiprocessor capable operating Systems available nowadays including of course, Linux and the BSDs so there'll be no shortage of options for desktop or server users. There will also be, as you would expect, several embedded OSs to choose from.
One feature the 8641D has is the ability to not only run multiprocessor operating systems but also to run an OS per core, bringing new meaning to "dual boot" systems in the process! Having two operating systems running independently has some very interesting possibilities for OS or application development though modified drivers will be required for any operating systems which utilise this feature. This also gives developers the ability to create an uber stable OS environment. If all the I/O goes via a primary OS on core 1 a secondary OS could be set up to run completely independently on core 2 with only minimal communication between them, even if the first OS completely fails and needs to reboot, the second OS is never affected. You could conceivably leave a task running on one core and reboot multiple times into different systems without ever stopping the task. Useful if you want to boost your RC5 score.
Who'll use it?
The 8641 / 8641D is expected to sample in the second half of next year so I don't expect to see products turning up for at least another year.
Apple's iBook would be an obvious target for this CPU as I think they'll look at the G5 for the PowerBook, however Apple could then find themselves in a situation where the iBook outperforms the PowerBook. They could however use the single core version of the chip in the iBook leaving the option of either the dual core 8641D or a G5 in the PowerBook. Of course as usual Apple will probably use higher clocked "P" rated parts which aren't generally advertised on the web site.
The 8641D and G5 will be strong in different areas so will not compete directly for the most part, the G5 is strong on floating point and like PC CPUs goes for high single threaded performance. The 8641D will give better overall system and multi-threaded performance with lower power consumption. The G5 is also 64 bit whereas the 8641 is 32 bit, Freescale do have a have a higher clocked 64 bit CPU in development but no details have been announced as yet.
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