I had a chance to sit down with OS vendor Wind River at ESC. We talked about many things, but I kept ending up on the same question: Why am I hearing so little about Linux? Part of the answer is that Linux is overkill for a lot of apps. If you don't need a sophisticated file system, network stack, and GUI, you probably don't need Linux. But that answer leaves me unsatisfied. More and more DSP systems need these and other features found in Linux. So why aren't people talking about it more?
I suspect that part of the problem is that Linux vendors over-promised and under-delivered in the early days. Five years ago, you heard that the OS was "free," but not that you would have to spend countless hours to get it running. Vendors claimed that you would have tons of software available from the desktop world, but much of this SW was useless for embedded apps.
Thanks to these and other problems, the first designers to try Linux got a nasty surprise. I wonder if they were burned so badly that they avoided Linux ever since. If this hypothesis is correct, it is highly unfortunate. Linux vendors like Wind River have made huge strides in making the OS an attractive option for DSP. The old problems are mostly history, and the vendors have added important new features that nobody was thinking about five years ago.
One of the coolest new features is virtualization, which lets you run multiple OSs side-by-side on the same machine. Virtualization lets you access all the good parts of Linux without giving up the things you need from your RTOS—such as deterministic responsiveness, high security, and the ability to run legacy code. Virtualization is already huge in servers. I think its going to become a big deal in embedded apps, too.
I think the other reason we're not hearing as much about Linux is that it has become "hidden" inside of middleware platforms like Android, LiMo, and Moblin. I suspect that the buzz about these platforms is drawing attention away from plain old Linux.
What do you think? Is Linux still over-hyped? Have you given up on it? Or are you a convert?