1) Control groups (cgroups): Cgroups was initially developed to limit resource usage in the Linux kernel. Memory, bandwidth, CPU usage can be controlled using cgroups, and it can be used to deny access to and monitor system resources. Red Hat’s Resource Management Guide has a great description with a lot of detail on how they work, check it out for more info. The developers are still working on improving how cgroups work, so report bugs and stay tuned!

2) KVM: It’s really the hypervisor that will be most supported by developers… so get ready to switch from Xen if you haven’t already. Christoph Hellwig gave a thorough talk on how KVM and qemu handle presenting local storage to the guest and what developers are doing in that area. Mike Day of IBM set out to debunk some myths about KVM that have held it up from being adopted more broadly. Some of his points were well-received by the audience, but there was a little dissension in the audience when he tried to claim that KVM and VMware were very similar because VMware’s VMKernel is largely based on the same Linux code… Audience members (who work at VMware) said no it’s not. It hasn’t been for a while.

3) Yocto Project: While you may not care much about embedded devices, who knows how the world (or your job) might change in the future? Besides, Linux is in everything if it’s electronic. The Yocto Project is the combined effort of all the major embedded chip vendors, embedded commercial Linux vendors, individual developers and OpenEmbedded to help developers not have to reinvent the wheel each time they go to create a new device. Check it out.

4) File systems: A great talk from Michael Rubin of Google provided details on why Google chose ext4 to deploy to replace ext2 (and a little about their process of doing it slowly so they didn’t lose all the data). XFS and ext3 were considered but dismissed, the former due to its complexity, the latter because it contained some of the same drawbacks as ext2. While Google chose ext4, Rubin seemed to have caught the buzz around btrfs, which just wasn’t “mature” at the time. With a three year transition from ext2 to ext4 though, I’m doubting Google will be looking to make another move any time soon. But if you’re looking at a file system upgrade, it may be worth looking into “butter.”

5) Open vSwitch: Open vSwitch is a network switch built for virtual environments and differs from traditional switches by exporting an external interface for fine-grained control of configuration state and forwarding behavior. There was a well-attended presentation on this technology and it’s certainly something to watch or look into if you are running large virtual environments and need more efficiency.

The most thorough, was Dale Strickland-Clark of Out-Think Ltd. He wrote a listing of why he loves Linux:

• Reliable – doesn’t slow down or break a month after being installed.
• Sensible security structure. It doesn’t get in the way of work.
• Work quickly with files. Konqueror and Dolphin are excellent file managers. Explorer is a mess.
• Full access to entire systems. Windows has bits even administrators are shut out of without a lot of work.
• Full function system without a GUI if you don’t need one for lightweight applications and servers.
• Community support that doesn’t try to rip you off.
• Multiple desktops let you split work functions logically.
• Full function, secure remote control with or without GUI.
• Excellent tools for diagnosing Internet/network issues standard on most distributions.
• Powerful batch languages with transparent (exe-like) invocation.
• Highly extendible and configurable user environment. Power users are empowered.
• Dead Linux systems can usually be recovered without a re-install.
• Use Linux on a memory stick to boot broken Windows machines to recover data.

Major Hayden a self-described “Linux guy” highlighted his top reasons:

• Makes old hardware usable
• Free
• Makes it so you can turn anything into a server
• No mouse required
• The people who use it and develop it genuinely care about the user experience.

One of our regular site contributors, Ron McCarty shared that his big reason is that Linux is a “solid operating system with a reliable TCP/IP stack, good server software, and it just runs!” What’s not to like?

Demonstrating the versatility of Linux, Jesse Casman, who is a bit of an international Linux and open source ambassador, shared that Linux is the best mp3 player for his car.

“Riocar was a British company that made a pull out Linux computer for your dashboard, you could connect it to your PC, load with mp3s, and rock and roll,” said Casman. “It still works — Really cool.”

Open source technologies like Linux wouldn’t be so successful if it weren’t for the developer love. One developer, Piotrek Tomiak, Eclipse Technologist said, “Linux is designed for programmers: it’s highly-customizable, fast, and has an outstanding console.”

Finally, neatly summing up his reasons for Linux adoration was Todd Williams of Genuitec: “It boots quickly, operates efficiently, and runs perpetually.”

What’s your favorite feature of Linux, why do you love it?

Purdie certainly fits the bill. As maintainer of the Yocto Project, he’s helped developers create custom Linux software regardless of hardware infrastructure. Recent experience has included his role as a core developer at OpenEmbedded, an embedded Linux architect at Intel’s Open Source Technology Center and a wealth of contributions to the Linux kernel. As a Fellow, Purdie will continue his work on the Yocto Project, OpenEmbedded and other embedded Linux projects while supporting The Linux Fellowship’s software initiatives.

Purdie joins a list of Linux Foundation Fellows that includes John Hawley and Linus Torvalds. Check out the full announcement of the appointment for more details.

Walking the floors at the Consumer Electronic Show (CES) with a surface look at the products won’t tell the true story of the impact of Linux. While there might be a few occasional mentions of Linux, for the most part the real story is what’s behind those e-Book readers, MP3 players and pretty much anything with the word “smart” in the name. Embedded Linux has staked its claim as the go-to choice for a wide array of electronic devices.

e-Book readers, Wi-Fi HDTV, and smart phones rely on Linux
This year’s CES saw an explosion of e-Book readers of all shapes and sizes. Only one of the offerings uses Windows Embedded (Plastic Logic Que) while the majority use some embedded Linux variant. Two offerings, the Spring Design Alex and Entourage eDGe, use Google’s Android. Wind River and MontaVista are the two leading vendors of embedded Linux and associated tools. Each counts at least one e-Book manufacturer as a customer.

The latest trends in HDTV and Blu-ray players include features like Wi-Fi connectivity, YouTube playback over wired or wireless Ethernet and remote control over Wi-Fi using an iPhone. Much of this new functionality has embedded Linux behind it. This includes everything from the networking code to connect with YouTube and stream Flash-based video to the on-screen display. The big win here for hardware manufacturers is the ability to leverage existing development tools and code to reduce their time to market.

In the smart cell phone market the lead story is Google’s Nexus Android-based handset. Android runs on top of the Linux kernel and represents a serious challenge to Apple’s iPhone. Google announced this week their own handset developed by HTC that would be sold directly to the public. Other vendors with Android-based devices include Dell, LG and Motorola.

Lenovo brings hot laptop and netbook offerings with Linux inside
On the computing front, Lenovo showed two innovative laptop/netbook offerings with Linux in the spec sheet. The Skylight (image right) is a sleek, curvy, under 2 lb. netbook with a Linux variant as the OS underneath. The core Linux comes from Thunder Software Technology headquartered in Beijing China. Lenovo did the user interface work themselves using the Clutter toolkit for the 3D effects and Google Gadgets. Lenovo also plans to offer a software development kit (SDK) for building custom applications on top of the Skylight OS.

The Skylight is targeted at mobile users looking for an easy way to keep up with e-mail, Facebook and Twitter, or to watch a movie in full HD it packs a Snapdragon processor, 10-hour battery life, 3G connectivity and your choice of color. Flash 10 will be supported out of the box for viewing the latest YouTube content. Lenovo envisions the Skylight appealing to the student crowd with their highly mobile and connected lifestyle. The Skylight will be available in Q1 of 2010 through direct sales and, potentially, at a subsidized price through a cell carrier.

Lenovo’s Ideapad U1 was another new product with a unique removable display that transforms from LCD monitor into a Linux tablet when you remove it from the laptop base. The base laptop sports an Intel Atom Core 2 Duo processor while the tablet/screen contains the same Snapdragon chip as the Skylight. Special software in the screen switches from display mode to tablet mode when detached from the base.

Just plug it in: Plug computing
Marvell Semiconductor introduced the concept of plug computing with their SheevaPlug platform in 2009. At this year’s CES there were multiple vendors showing products based on the same chipset including Globalscale, Ionics and TonidoPlug. Each of these devices is about the size of a typical wall-wart power plug but typically contain a CPU, memory, Ethernet and USB interface. Uses include a Network Attached Storage (NAS) device, home media server, network backup utility and more.

The bottom line on Linux in the consumer electronics marketplace is cost. Linux helps reduce the overall cost and the time needed to bring new product to market. It also provides familiarity for developers looking to deliver new applications to the mobile device space and to manufacturers needing hardware and software engineers to build the next model of their consumer devices. Overall, Linux is doing quite well, even if you can’t tell it’s there.

ABOUT THE AUTHOR: Paul Ferrill has a BS and MS in electrical engineering and has been writing about computers for over twenty years. He’s had articles published in PC Magazine, PC Computing, InfoWorld, Computer World, Network World, Network Computing, Federal Computer Week, Information Week, and multiple Web sites.

More on Linux at CES:
Linux dot com: When one Linux project wins, all Linux triumphs

ars technica: Tux takes a bow: Linux makes its presence known at CES

Linux Journal: Hunting Linux at CES