I have an 8 core dual socket AMD machine. I noticed CURRENT was having issues saturating it under load until a week or so ago, not sure what that was about. I do a buildworld -j(NTHREADS * 2 + 1) and it executes very quickly, limited primarily by disk i/o. ZFS rocks on this thing, as does mysql/postgres or anything else that is happy with threads.
I do force multithreaded make jobs for ports, with 0 problems so far (not since mid-2011). I usually only see one thread getting hammered with older software that isn't thread aware. Usually load is split well.
The fact of the matter is that the future lies in more cpus with deeper c-states. It allows better power savings based on demand than two to four all-powerful cores. Even with deep c-states, the resolution for demand vs power saving is very low. I think the change will be very rapid as NUMA issues are resolved as well as software that is thread-averse gets fixed. There will always be software that benefits from one fast core more than many slower ones, but that pool of software is shrinking.
But like I said, I'm just as happy with my dual i7 (4 threads). It kills single threaded stuff, and most stuff is HT aware (FreeBSD is) so it doesn't bog down two fake cores on one die before giving jobs to the other die. But it doesn't have ECC, which is a downer. Personally for intel I really like the i3's that can run ECC in server boards. They're plenty fast for a file server or web server, and they run a consistent temperature as they don't have a "turbo" (AKA lava) mode.
I do force multithreaded make jobs for ports, with 0 problems so far (not since mid-2011). I usually only see one thread getting hammered with older software that isn't thread aware. Usually load is split well.
The fact of the matter is that the future lies in more cpus with deeper c-states. It allows better power savings based on demand than two to four all-powerful cores. Even with deep c-states, the resolution for demand vs power saving is very low. I think the change will be very rapid as NUMA issues are resolved as well as software that is thread-averse gets fixed. There will always be software that benefits from one fast core more than many slower ones, but that pool of software is shrinking.
But like I said, I'm just as happy with my dual i7 (4 threads). It kills single threaded stuff, and most stuff is HT aware (FreeBSD is) so it doesn't bog down two fake cores on one die before giving jobs to the other die. But it doesn't have ECC, which is a downer. Personally for intel I really like the i3's that can run ECC in server boards. They're plenty fast for a file server or web server, and they run a consistent temperature as they don't have a "turbo" (AKA lava) mode.
