What is your experience with Sun CoolThreads technology?

Question

My project has money that needs to be spent before the end of the fiscal year, and we plan to replace the Sun-Fire-V490 server that we had for several years. One of the options we are considering is CoolThreads technology. All I know is the marketing of the Sun, which cannot be 100% impartial. Has anyone really played with one of them?

I suspect that this will not be practical for us, since we do not use threads or virtual machines, and we cannot spend a lot of time refining the code. We create a ton of processes, but I doubt CoolThreads will help there.

(And yes, the money will be better spent on bonuses or something like that, but that will not happen.)

Answer 1

Disclosure: I work for Sun (but as an engineer in client software).

You do not need a multithreaded code to use these machines. Having multiple processes will use multiple hardware threads across multiple cores.

Older T1 processors (T1000 and T2000 boxes) had only one FPU, and they were not suitable for floating point tasks greater than 1%. The new T2 and T2 + processors have FPUs per core. This is probably still not very important for massive floating point flexion, but much more respectable.

(Note: Hyper-Threading Technology is a trademark of Intel. Sun uses the term Chip MultiThreading (CMT).)

Answer 2

IIRC coolthreads technology refers to the fact that instead of just increasing the clock speed to increase performance, they now consider several core processors with hyperthreading, which gives you a lot of processors on a single chip. In general, the availability of processed power is higher, but without the additional requirements for electricity and air conditioners that you expect (hence it's cool). Its usefulness definitely depends on what you plan to run on it. If you use Apache with a kernel with multiple threads, it will love it, since it can run separate response threads on separate processor cores. If you just run processes with a single thread, you will get a slight increase in performance in one processor box, but not so large (any old-fashioned CGID processes without mod_perl / mod_python will still share the processor). If your application consists of one process with one thread running on a box, you will get very little improvement on a single-core processor running at the same speed.

Peter

Edit:

Oh and for the test. We compared the T2000 in our server farm with our current V240 (maybe it was a V480 that I don’t remember). The T2000 took a load of 12-13 Older cells in real testing without any spoofing of the operating system. As I said, Apache loves this :-)

Answer 3

We used the Sun Fire T2000 for my latest system. The crates themselves far exceeded our power requirements in terms of processing power. For us, this decision was based on lower energy consumption and space consumption. We successfully launched WebSphere 6, Oracle 10g, and the SunONE Directory server in the same field.

Answer 4

My information may be a bit outdated (the latter was used by these servers 2 years ago), but, as I recall, one big problem was that all the cores on the same CPU all shared the same FPU, so if your code did a lot of floating point (we did the GIS), FPU was a massive bottleneck, and you did not get much benefit from the large number of threads.

Answer 5

For any process with high parallelism, these machines (e.g. t1000 / t2000) are great for their cost. I worked the oracle on them for about 18 months and it works great.

If the task is a single process with one thread / one, then you will be better off working with a high-speed dual-core Intel Core i4 processor.

If your application has many threads / many processes, then these machines are likely to be great for it.

Best of all, Sun will send you 60 days to evaluate, this is what we did before doing this, ended up getting 2 t2000 and recently acquired another 4 t1000.

Answer 6

Yesterday, he hit me that our main processes are not multithreaded, but the machine in question has a bunch of system processes. In particular, it works as an NFS server. It seems that starting hundreds of processes will be useful for all of these cores.

I'll see if we can first get a demo for testing.

Answer 7

Sun sold Niagra cars to be all things for everyone. They really have their place: the best services are web services. We ran Oracle on some T2000s and worked well for highly parallel operations. But machines fall on one-sided operations, the performance of which is rather poor. If you have floating point work, look elsewhere. Even newer chips with A FPUs per core are inadequate. In addition, these machines cannot knock on the corporate class for a long time, and we had problems with reliability. Multi-core technology is more an advertisement than a substance. A Sandia National Lab study on this subject showed that four to eight cores belong to first-class functions and that the 16-core chip has the same throughput as the dual-core chip. Thus, a 16-core chip is a waste of big money. In addition, as the number of cores increases, the clock speed decreases due to the thermal wall. Most manufacturers will probably install on quad-core processors until the memory technology improves (you cannot save 16 cores with memory and most cores are stuck). Finally, given the chaos in Sun, you'd better look elsewhere.