X

USB 2 arrives in Linux test version

Linus Torvalds, founder and leader of the operating-system project, releases the newest version of the core software.

Stephen Shankland Former Principal Writer
Stephen Shankland worked at CNET from 1998 to 2024 and wrote about processors, digital photography, AI, quantum computing, computer science, materials science, supercomputers, drones, browsers, 3D printing, USB, and new computing technology in general. He has a soft spot in his heart for standards groups and I/O interfaces. His first big scoop was about radioactive cat poop.
Expertise Processors, semiconductors, web browsers, quantum computing, supercomputers, AI, 3D printing, drones, computer science, physics, programming, materials science, USB, UWB, Android, digital photography, science. Credentials
  • Shankland covered the tech industry for more than 25 years and was a science writer for five years before that. He has deep expertise in microprocessors, digital photography, computer hardware and software, internet standards, web technology, and more.
See full bio
Stephen Shankland
3 min read
The faster version 2.0 of the Universal Serial Bus connection technology, the center of some controversy with Windows, has been incorporated into the latest test version of Linux.

Linus Torvalds, founder and leader of the Linux operating-system project, released version 2.5.2 of the "kernel," or core software, Monday, including initial support for USB 2.0.

Linux may have lost its allure as a get-rich-quick scheme for would-be entrepreneurs, but the largely volunteer programming community that advances the core software is still functioning.

USB 2.0 enables data-transfer speeds of 480mbps--40 times the speed of the USB 1.1 that prevails in today's computers and peripheral devices, such as printers or digital cameras.

USB 2.0 support isn't generally built into computers; the competing FireWire standard is more common for high-speed connections to video cameras, hard drives or other devices that need to transfer data faster.

Operating-system support is a key requirement for unlocking the promise of new technologies. Without that support, it's much harder for a given technology to gain enough market presence to survive.

Microsoft has written support for USB 2.0 and made the software available to computer manufacturers, but the latest operating system, Windows XP, doesn't support the technology. Some viewed the slower adoption as a problem for USB.

Microsoft has said the USB 2.0 upgrade will be available early this year through its Windows Update online software archive.

The USB support in the world of Linux is much more freewheeling than at Microsoft. The Linux USB software has been created by a largely self-appointed team of programmers, who feed batches of code to the main kernel project.

Greg Kroah-Hartman maintains the USB software, and David Brownell has been leading the USB 2.0 work. Companies also help out: Randy Dunlap from Intel has worked hard on USB for Linux, while Compaq Computer contributed code to let devices be plugged or unplugged while the computer is still running.

USB 2.0 devices available include hard disks from La Cie and Maxtor as well as CD-RW drives from Iomega, La Cie, Sony, Yamaha, Plextor and others.

The creation of Linux takes place in two software versions: even-numbered point releases for real-world use--the 2.4 "production tree"--and odd-numbered point releases for trying out new software--the 2.5 "development tree."

Though the USB 2.0 support is built into the 2.5 version, a software patch for the present 2.4 version also is available. This "backporting" technique is a common way to move features tested in the development version into the production version.

The 2.5.2 kernel also has a new "scheduler," the essential part of an operating system that keeps track of what processes are underway. The scheduler, introduced by Red Hat employee Ingo Molnar, is intended to improve performance on high-end servers with many processors.

The production version of Linux also is ratcheting forward. The latest version, 2.4.17, includes support for "hyperthreading," a feature that lets a single Pentium 4 CPU do most of the work of two separate CPUs.

Torvalds named Marcelo Tosatti, an 18-year-old programmer with Brazilian Linux company Conectiva, to maintain the 2.4 kernel software.