The instruction width doesn't change the number of instructions you can run at any given time. Certain operations can be done more efficiently (for example, adding small numbers can be done in-instruction, rather than having to load stuff into registers first), but in general it's not going to matter. You're not going to magically get parallelism with 64-bit.
And it has nothing to do with Java (or at least very little). Servicing an HTTP request is pretty much a top-to-bottom procedure, there isn't a way to easily divide it up into bits of work that can be run in parallel. But since HTTP servers are typically servicing multiple concurrent requests, the overhead of trying to parallelize a single request is hugely outweighed by simply parallelizing separate requests. If you've got a multicore, multiprocessor machine, it's exceptionally unlikely you're going to be one request at a time, so trying to optimize that use case is of little value. To go back to your original scenario. If 1 request to your machine with the 5540s takes 261ms, then I'd expect 16 simultaneous requests to also take about 260ms. The cores/processors will allow those 16 requests to all run in parallel with all the CPU they can use. Contrast this with your 5160s, which can run 1 request in 196ms, but should take around 392ms to service those same 16 concurrent requests (because it can service 8 at a time, so the second 8 wait while the first 8 are processed, and then they get some CPU). And it's probably actually worse than that because unless you have your JVM/CF tuned to your request load there will probably be context switches between threads so you'll loose a bit of efficiency trying to run 16 requests on 8 execution threads. cheers, barneyb On Wed, Apr 7, 2010 at 2:41 PM, John Foster <jfos...@turbosquid.com> wrote: > > Do you think a 64 bit OS or CF9 would allow my apps to better utilize newer > CPU's , or would I still be bottlenecked by java to a single thread / request? > > ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~| Want to reach the ColdFusion community with something they want? Let them know on the House of Fusion mailing lists Archive: http://www.houseoffusion.com/groups/cf-talk/message.cfm/messageid:332739 Subscription: http://www.houseoffusion.com/groups/cf-talk/subscribe.cfm Unsubscribe: http://www.houseoffusion.com/groups/cf-talk/unsubscribe.cfm
