Search results
Results From The WOW.Com Content Network
CPU time (or process time) is the amount of time that a central processing unit (CPU) was used for processing instructions of a computer program or operating system. CPU time is measured in clock ticks or seconds. Sometimes it is useful to convert CPU time into a percentage of the CPU capacity, giving the CPU usage.
The Time Stamp Counter was once a high-resolution, low-overhead way for a program to get CPU timing information. With the advent of multi-core/hyper-threaded CPUs, systems with multiple CPUs, and hibernating operating systems, the TSC cannot be relied upon to provide accurate results — unless great care is taken to correct the possible flaws: rate of tick and whether all cores (processors ...
Further, a "cumulative clock rate" measure is sometimes assumed by taking the total cores and multiplying by the total clock rate (e.g. a dual-core 2.8 GHz processor running at a cumulative 5.6 GHz). There are many other factors to consider when comparing the performance of CPUs, like the width of the CPU's data bus , the latency of the memory ...
24×10 3: AN/FSQ-7 Combat Direction Central, 1957 [2] 30×10 3: IBM 1130 commercial minicomputer, 1965 [2] 40×10 3: multiplication on Hewlett-Packard 9100A early desktop electronic calculator, 1968; 53×10 3: Lincoln TX-2 transistor-based computer, 1958 [2] 92×10 3: Intel 4004, first commercially available full function CPU on a chip ...
[1] [2] [3] An idle computer has a load number of 0 (the idle process is not counted). Each process using or waiting for CPU (the ready queue or run queue) increments the load number by 1. Each process that terminates decrements it by 1. Most UNIX systems count only processes in the running (on CPU) or runnable (waiting for CPU) states.
ACPI 1.0 (1996) defines a way for a CPU to go to idle "C states", but defines no frequency-scaling system. ACPI 2.0 (2000) introduces a system of P states (power-performance states) that a processor can use to communicate its possible frequency–power settings to the OS. The operating system then sets the speed as needed by switching between ...
The term can also refer to the condition a computer running such a workload is in, in which its processor utilization is high, perhaps at 100% usage for many seconds or minutes, and interrupts generated by peripherals may be processed slowly or be indefinitely delayed.
Processor manufacturers usually release two power consumption numbers for a CPU: typical thermal power, which is measured under normal load (for instance, AMD's average CPU power) maximum thermal power, which is measured under a worst-case load; For example, the Pentium 4 2.8 GHz has a 68.4 W typical thermal power and 85 W maximum thermal power.