Linux coders tackle power efficiency
Maybe you’d be better off if you didn’t spend so much time looking at your watch.
That, loosely speaking, is the rationale behind a significant change at the heart of Linux that programmers hope will make the open-source operating system more efficient. New versions of the operating system are being endowed with a “tickless” kernel that forsakes traditional computer time-keeping in an effort to keep the processor in a somnolent, low-power state.
Power efficiency is something every operating system could use. For Linux, efficiency could make the operating system more competitive with Windows on portable computers by extending battery life, and on servers that typically run 24 hours a day, it could cut growing power costs.
The tickless kernel isn’t the only effort under way. Intel released software called PowerTop in May that makes it easier to find out what software is needlessly keeping a computer’s processor on high alert.
“It makes a lot of sense,” Illuminata analyst Gordon Haff said of the power-saving work. “Raw, flat-out horsepower is less and less what the game’s about–especially on laptops, which are becoming more common.”
Some Linux developments take years to arrive, but the tickless kernel is now making its way into the Linux mainstream.
“The re-engineering has mostly been done,” said Linux leader Linus Torvalds of the new kernel. And for higher-level software, PowerTop has been “invaluable,” he added. “A lot of people and (Linux) distributions are actually interested in this, so the user applications do seem to be getting fixed.”
There’s more work to be done, but the progress has been measurable, said Arjan van de Ven, a longtime kernel programmer now working at Intel. “What we see in our lab today is that Linux on a laptop consumes 15 percent to 25 percent less power during idle than a code base of about three months ago,” he said.