On 12/09/2013 7:59pm, Giampaolo Rodola' wrote:
Given that multiple processes cannot take any advantage of hyper threading technology then maybe it makes sense for multiprocessing to expose a physical_cpu_count() function in order to preemptively figure out how many processes to spawn.
Do you have a reference? Wikipedia may not be reliable, but it seems to think otherwise: Hyper-threading works by duplicating certain sections of the processor— those that store the architectural state— but not duplicating the main execution resources. This allows a hyper-threading processor to appear as the usual "physical" processor and an extra "logical" processor to the host operating system (HTT-unaware operating systems see two "physical" processors), allowing the operating system to schedule two threads or processes simultaneously and appropriately. ^^^^^^^^^ -- Richard