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Intel Details Upcoming Gulftown Six-Core Processor
MojoKid writes "With the International Solid-State Circuits Conference less than a week away, Intel has released additional details on its upcoming hexa-core desktop CPU, next gen mobile, and dual-core Westmere processors. Much of the dual-core data was revealed last month when Intel unveiled their Clarkdale architecture. However, when Intel set its internal goals for what its calling Westmere 6C, the company aimed to boost both core and cache count by 50 percent without increasing the processor's thermal envelope. Westmere 6C (codename Gulftown) is a native six-core chip. Intel has crammed 1.17 billion transistors into a die that's approximately 240mm sq. The new chip carries 12MB up L3 (up from Nehalem's 8MB) and a TDP of 130W at 3.33GHz. In addition, Intel has built in AES encryption instruction decode support as well as a number of improvements to Gulftown's power consumption, especially in idle sleep states."
Cores are like girls in 'hot sluts gone wild' scenes - after a certain point you might hardly notice if there's even more of them, but you'd never say "no" to an increase.
Cores are like girls in 'hot sluts gone wild' scenes - after a certain point you might hardly notice if there's even more of them, but you'd never say "no" to an increase.
But my "operating system" can only deal with one hand- I mean core- at once!
Wrong question. When was the last time my computer was running a single thread that could use 100% CPU for more than a few milliseconds. Answer: All the time. For example whenever I open Slashdot with Firefox. I rather have less cores at higher speed than more cores.
1.17 billion transistors into a die that's approximately 240mm sq
That's a big chip.
240 mm sq, that's 15.49mm x 15.49mm
Can most programmes really be written to take advantage of so many cores?
Yup.
Got a Core i7-920 running at 3.2GHz at home - OS is 64-bit Kubuntu 9.10.
Yesterday I had five two-hour videos I wanted to render to DVD5 format - four were .avi and one was .mp4.
Launched five instances of DeVeDe to render the video and create the DVD file structure and did all five at the same time - then left for work. Took an hour and twelve minutes and the machine didn't melt, explode or let any of the magic smoke out of the box.
Even if an application isn't multithreaded the OS is - so even running a single task a multicore processor will give you a performance boost.
A Core i7 has four cores that'll run two threads each - presents as eight processor cores to the OS. I have no problem using them all ;-)
we see things not as as they are, but as we are.
-- anais nin
Most programs can't be written to take full advantage of even one core. Most of the things that you do on a computer will run happily on a 1GHz CPU and still not bring usage over 50% more than occasionally. Most of the things that will tax a modern CPU can be made parallel, so will scale quite well to a number of cores. Even if your processor intensive task isn't using multiple cores, you still benefit a bit from being able to move everything else onto another core. With the recent Intel chips you also have 'Turbo Boost' (horrible name) which underclocks some cores while overclocking others, giving one core a speed boost for that CPU-eating single-threaded app while keeping the power usage and heat generation output. To prevent hotspots on the die, you can move the process around between the cores, giving each a boost for a little while.
I am TheRaven on Soylent News
Porting libdispatch requires a generic event delivery framework, where the userspace process can wait for a variety of different types of event (signals, I/O, timers). On Darwin, Apple used the kqueue() mechanism that was ported from FreeBSD, so it's quite easy to port the code to FreeBSD (just #ifdef the bits that deal with Mach messages appearing on the queue). Kqueue is also ported to NetBSD and OpenBSD, so porting it to these systems will be easy too.
Solaris and Windows both have completion ports, which provide the same functionality but with different interfaces. Porting to Solaris would require replacing the kqueue stuff with completion port stuff. Porting to Windows would ideally also require replacing the pthread stuff with win32 thread calls. Even Symbian has a nice event delivery framework that could be used, although I'm not sure what the pthread implementation is like in the Symbian POSIX layer.
Linux is the odd system out. All different types of kernel events are delivered to userspace via different mechanisms, so it's really hairy trying to block waiting until the next kernel event. This also makes it harder to write low-power Linux apps, because your app can't spend so long sleeping and so the kernel can't spend so much time with the CPU in standby mode.
If you don't need the event input stuff (which, to be honest, you do; it's really nice), you can use toydispatch, which is a reimplementation that I wrote of the core workqueue model using just portable pthread stuff.
It also adds some pthread extensions for determining the optimal number of threads per workqueue (or workqueues per thread, depending on the number of cores and the load), but these are not required. The FreeBSD 8.0 port doesn't have them; they were added with FreeBSD 8.1.
I am TheRaven on Soylent News
If you left for work, would it have really made any difference to you if it took five times as long?
Well, yeah. I wouldn't have been able to brag about it ;-)
we see things not as as they are, but as we are.
-- anais nin
Maybe GTA 4 is a very specific app for you.To me, GTA 4 is an important application :) :)
And that game, my friend, requires a quad-core CPU. Which I don't have at the moment, and even with my Intel E6550 overclocked from 2.66 to 3.6 GHz the game runs at 25-35 FPS at 1680x1050, with both cores at 100%.
I used to have the same approach (multicore is dumb) but now it's a thing of the past.
There are more and more apps and games out there who take advantage of multicore, not to mention that operating systems (such as Windows 7) are better at allocationg sepaarte cores for single-core applications to balance the load.
Therefore, while I don't dismiss the need of having a multicore CPU, in the end it's all about balancing your investment against the benefits. If you need a 6-core CPU and it doesn't cost a kidney and a lung, then get it. Regardless of your decision as a customer, there's always a good thing in this sort of advancements: new stuff pushes down prices for older stuff
...gis sdrawkcab (usually not responding to ACs; don't bother posting as AC)
What?
AES acceleration will be useful for VPNs, serving SSL websites, VoIP, full disk encryption ... and so on.
Wrong question. When was the last time my computer was running a single thread that could use 100% CPU for more than a few milliseconds. Answer: All the time. For example whenever I open Slashdot with Firefox. I rather have less cores at higher speed than more cores.
Really? So one thread wasn't reading the network traffic, one wasn't parsing the markup, and a third putting things up on the screen? At the same time the page wasn't being saved to your browser cache, while your e-mail program was querying the server for new mail, and cron was checking to see if there were jobs to run this minute? If you're on Windows, all of these activities were probably scanned by anti-virus.
There's a lot going on in a modern system:
$ ps -ef | wc -l
146
Why put AES on-board?
They're not: they're putting extra instructions on-board which help implement AES more efficiently. They may also allow you to implement other algorithms more efficiently, though I haven't looked at them in enough detail to be sure.
I thought AES was relatively fast as encryption algorithms go.
That still doesn't make it fast at an absolute level. Particularly when you're doing full-disk encryption with user account encryption on top and IPSEC on all your network connections.
Most of the things that you do on a computer will run happily on a 1GHz CPU and still not bring usage over 50% more than occasionally
Speak for yourself.
It's official. Most of you are morons.
Why put AES on-board?
They're not: they're putting extra instructions on-board which help implement AES more efficiently. They may also allow you to implement other algorithms more efficiently, though I haven't looked at them in enough detail to be sure.
The instructions perform a single round of AES (which has 10-14 rounds depending on key size), either encrypting or decrypting. Certain other algorithms such as Lex, Camellia, Fugue and Grostl use AES S-boxes in their core, and can probably benefit from these instructions. However, they will not achieve nearly so much a speedup as AES.
The AES instructions themselves will approximately double the speed of sequential AES computations. This is very unimpressive; VIA's AES instructions are much faster. They will also make it resistant to cache-timing attacks without losing speed, which is unimpressive because you can already do this on Penryn and Nehalem. The low speed results from the AES instructions having latency 6; if you can use a parallel mode (GCM, OCB, PMAC, or CBC-decrypt, for example) then the performance should be 10-12x the fastest current libraries. Hopefully, this will cause people to stop using CBC mode, but perhaps I'm too optimistic.
Intel also added an instruction called PCLMULQDQ which does polynomial multiplication over F_2. If it's fast (I can't find timing numbers, but hopefully it's something like latency 2 and throughput 1) then it will be very useful for cryptography in general, speeding up certain operations by an order of magnitude or more. This is more exciting to me than the AES stuff, because it might enable faster, simpler elliptic-curve crypto and similarly simpler message authentication codes. Unfortunately, these operations are still slow on other processors, so cryptographers will be hesitant to use them until similar instructions become standard. If the guy you're communicating with has to do 10x the work so that you can do half the work... well, I guess it's still a win if you're the server.
I thought AES was relatively fast as encryption algorithms go.
That still doesn't make it fast at an absolute level. Particularly when you're doing full-disk encryption with user account encryption on top and IPSEC on all your network connections.
AES is fast for a block cipher, but modern stream ciphers such as Salsa20/12, Rabbit, HC and SOSEMANUK are about 3-4x faster. (In other words, they are still faster than AES in a sequential mode on Westmere.) AES is still competitive, though, if you can use OCB mode to encrypt and integrity-protect the data at the same time.
The fastest previous Intel processor with cutting-edge libraries in the most favorable mode could probably encrypt or decrypt 500MB/s/core at 3-3.5GHz. This is fast enough for most purposes, but in real life with ordinary libraries you'd probably get a third of that. So this will significantly improve disk and network encryption if they use a favorable cipher mode.
Cred: I am a cryptographer, and I wrote what is currently the fastest sequential AES library for Penryn and Nehalem processors. But the calculations above are back-of-the-envelope, so don't depend on them.
I hereby place the above post in the public domain.