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Cpu

Central Processing Unit

The brain of the computer - The CPU is responsible for executing instructions of computer programs and controlling the other components of the computer system. - It performs arithmetic and logical operations on data, retrieves and stores data in memory, and communicates with other components of the computer (such as the memory, input/output devices, and secondary storage devices)

CPU addresing

set in bits - Word how big of a chunk of memory cpu can take and operate on - Thats why Therese the x64 architecture - Coputer can operate only on 64 bits at a time

[!note] x32 can only operate on 4Gigs of memory … Now u can operate on 20 exabyte

Cpu times (Subdevisions)

User - Amount of time CPU was busy executing code in user space

System - amount of time the CPU was busy executing code [[Kernel|Kernel space]].

Idle(for the whole system only) - amount of time the CPU was not busy - amount of time it executed the System Idle process. - Idle time actually measures unused CPU capacity.

Steal(for the whole system only) - on virtualized hardware, is the amount of time the operating system wanted to execute, but was not allowed to by the hypervisor. - This can happen if the physical hardware runs multiple guest operating system and the hypervisor chose to allocate a CPU time slot to another one.

[[mpstat]]

CPU process priorities

nice - reniceCompitaltion process garbage_collector_c