Reduce the Linux kernel empty cycle to reduce system energy consumption skills

If you don't spend more time looking at your watch, you will have more time.

In layman's terms, this is the rationale for an important change in the Linux kernel, and programmers hope that this change will improve Linux's efficiency. The new Linux operating system will use a "tickless" (no empty loop) kernel, allowing the processor to run in a low-power state.

Energy consumption is very important for all operating systems. For Linux, by extending battery endurance, low energy consumption can improve its ability to compete with windows in the notebook and server sectors, reducing the cost of electricity.

The tickless kernel is not the only plan to improve the efficiency of Linux energy use. In May, Intel released a software named PowerTOP. ' It's very important, ' said Illuminata, an analyst at the Energy Conservation Program.

Some Linux development takes several years to be accepted by the mainstream market, but the "tickless" kernel is entering the mainstream Linux version. When it comes to the new kernel, Linux's father, Torvalds, says most of the redesign work is done. For advanced software, he says, the value of PowerTOP is immeasurable.

Linux kernel programmer Van der Van says that while there is more work to be done, considerable progress has been made. He says lab tests show that Linux laptops consume 15% to 25% less energy than the code used 3 months ago.

The processor consumes more than 100 watts of energy, although it is not the only large energy consumer in the computer. In addition, the cooling fan also requires electricity to blow away the heat generated by the processor. But in recent years, chip makers have made it possible for processors to operate in low energy conditions. When the processor clock frequency drops, the voltage will also decrease, and the energy consumption will decrease.

But the OS kernel does not do well enough to save energy. One of these is that software often unnecessarily makes the operating system kernel "alert". Another problem is that the kernel itself wastes energy. Intel's software is able to identify the first type of problem, and the "tickless" kernel solves the second type of problem.

The 2.6.21 Linux kernel supports "tickless" technology, which has been applied to fedora

7. Van der Van says the 2.6.21 Linux kernel can save a lot of energy. In the most energy-efficient state, the Intel mobile chip consumes 1.2 watts, and "Tickless" enables the processor to run in the most energy-efficient state.

The tickless kernel still records time, but it takes a different approach. No longer frequently checking whether there is work to be done, and when it is known that there is work to be done, the kernel schedules the hardware to issue an interrupt request.

The tickless kernel has another indirect benefit in terms of energy efficiency: better use of virtual technology means that virtual software will not be unnecessarily interrupted.

Phoronix website Editor Michael found that the Tickless kernel was able to reduce energy consumption from 28 watts to 26 Watts at IBM configuration Pentium M and the ThinkPad R52 running Fedora 7. He says the tickless kernel, coupled with chip-level energy-saving technology, can prolong battery endurance and reduce calorific value