Linux ups Web cams to Wi-Fi

18.01.2007
By its own developers' admissions, Linux supports more hardware devices out-of-the-box than any other operating system but that won't stop a slew of new drivers being added in upcoming releases.

Two years after his 2005 Kernel Report, Colorado-based Linux developer Jonathan Corbet returned to Australia's linux.conf.au conference in Sydney this week to discuss recent enhancements to the open source operating system.

Corbet said the next release, kernel 2.6.20, will include a whole lot of new drivers, including a USB vision driver which will bring support for USB Web cams.

"Linux hardware support is better than ever and it supports more hardware natively out-of-the-box than any other operating system," he said. "The biggest problem is vendors that won't release drivers or specifications."

Corbet said traditionally wireless networking has been poorly supported but is getting better and the current implementation is being replaced with a networking stack with "proper 802.11 which is slowly making its way into mainline."

There are also people working on porting the BSD Atheros Wi-Fi drivers to Linux.

"Within a year or so people will not be complaining about wireless drivers anymore," Corbet said.

With disks getting bigger and comparatively not that much faster, Corbet said the time it takes to check file systems is getting longer and Linux needs more advanced file systems to deal with this trend.

"Disks are not getting more reliable [and] our file systems are old," Corbet said. "Most of the action is with ext4, which is in the mainline kernel."

Corbet said ext4 has a different way to lay out blocks which is better for large disks and the 48-bit block size will get over the 8TB limit.

On the competing file system, Reiser 4, Corbet said it has a lot of interesting ideas but it is still stalled and unless someone adopts it, it may fade away.

Another area garnering a lot of interest is virtualization, for which a number of solutions are being actively worked on for Linux.

Corbet said the biggest issue with virtualization is all the competing methods want to be supported in the mainline kernel with their own hypervisor but "we are never going to include all, just one."

"We now have one called paravirt_ops which isolates low-level operations," Corbet said. "This is the interface that has been adopted for hypervisor access and people are starting to use it."

The popular Xen is a full paravirtualization solution that has generated "a lot of hype" but its path into the kernel has been slow for a lot of reasons, Corbet said, and may get even slower.

A separate dev that went into 2.6.20 is Kernel Virtual Machine, or KVM, which supports hardware virtualization.

"It is a full virtualization solution but people are doing paravirtualization with it as well," Corbet said. "You'll see a lot with KVM in the future."

In addition to virtualization, there is another method called containers, like Linux-Vserver and OpenVZ, which "are a lighter approach."

Containers create a set of "walls" that run on the same kernel to isolate processes leading to better performance but the amount of work to get into kernel is non-trivial.

On the general kernel development process, Corbet said changes are happening faster than ever before and new features are being added to the kernel in months, not years.

"The process works a lot better now," he said. "Some say the new development model places too much emphasis on features and we are squandering our reputation for putting out high-quality kernels. It's hard to demonstrate whether the kernel is becoming more or less reliable."

Corbet encouraged organizations that use Linux to get more involved in its development by saying part of the payment you have to make for free software is to be part of the development and testing process.

"We don't have any five-year road maps as analysts are saying," he said. "There is no ability to force work from anybody but there are no limits on people's imagination."