Enable or disable logical cores, or display your current CPU topology.
smt-manager.pl - View current status of CPU topology or set logical cores to offline or online.
smt-manager.pl [options] --help Prints this help. --online Enables all logical CPU cores. --offline Disables all logical CPU cores. --manual Display man page of this script.
--help Prints standard help information and options that are available. --online Attempts to enable all logical cores if they are already offline. If they are not offline, no changes will be made and no secondary topology print out will occur. --offline Performs the opposite action as --online. --manual Displays help page as a man page and also displays description and summary.
This script provides the user details about whether each CPU is physical or logical. When provided an optional parameter, the logical CPUs can be enabled or disabled. Why would one want to disable logical cores? Logical CPU cores with a high nice value steal more CPU time than a physical core. This is noticeable when multitasking heavily, for instance, building a kernel with 8 cores as a very nice (+20) task while running a greedy single threaded application. By disabling the logical cores, the behavior and responsiveness of the system will be more predictable, but throughput will drop as a whole for heavy multi- threaded batch jobs.