LinuxWorld: Stronger I/O & VM Coming Soon to Linux
Mark Brunelli, News Editor writes "Tim Witham, CTO of Open Source Development Labs and a featured speaker at LinuxWorld, says the next Linux kernel will feature improved input/output and virtualization capabilities. Said Witham: 'Enabling virtualization is a big win [for Linux 2.6] as it allows IT shops to start their development cycles for a technology they will be looking at deploying within the next year or so. There has been lots of good work done with regard to system scalability, memory management, disk I/O, process and thread scalability. Also, work done for availability, like a greatly improved multi-path I/O [were victories].'"
User Mode Linux is in 2.6, however, I believe they are referring to "Xen" which is a separate "arch" (like PPC, x86, SPARC). It is essentially an "arch" all it's own so that it can implement the low level details it needs to provide to the hosted OS's, but it has to run on top of a standard Linux kernel. It's an interesting concept.
Kirby
No Xen cannot virtualize/host any OS.
Instead the OS must be modified to support it. If you look at the Xen homepage you'll see more details.
Whilst this doesn't diminish the usefulness of the project it does mean you cannot host an XP installation - like you can with Qemu , or the commerical software VMWare.
I have used Qemu extensively in the past to host installations of Windows upon my Debian machine - whilst it is not as fast as Xen promises to be it is the best around at the moment (short of spending cash!)
Shouldn't the kernel tell the task to slow up when you're getting toward 2/3 (or 50%, 75%, 80% etc.) of the available memory pages? Would boot-up tests that store data-rate metrics for the available storage allow the system to slow down tasks likely to fill the memory pages before the disks can catch up which would allow the system to retain 'teh snappy'?