One-Machine Linux Cluster

An AC wrote: Forget Beowulf ^? clusters, Jacques Gelinas has made available a kernel patch to enable many virtual servers running on the same machine, even the same kernel. Read his original message posted to the Linux kernel list." Imagine what this will mean for hosting companies...

Comments

Beaowulf not the target audience

[Genady]

This has just about zero to do with clustering, if anything this is the opposite of clustering. However this IS very very interesting for Web Hosts and just about anyone else that wants to create and maintain multiple environments for developement, test, etc. Image, being able to carve up a mid-range machine like you can an S390 (or other Mainframe class machine Like Sun's E10/15K). So suppose IBM takes this an runs with it. Linux is already ported to RS/6000 and AS/400, now you could get 8 processors of RS/6000 goodness, run production on 4 processors, Test on 2 processors, and Dev on 2 processors.

The devil will be in how you refresh test and dev from production, but that can probably be done inside Logical Volume Manager.

This is very very cool stuff it will be very ineresting to see how it stacks up against the big boys in Virtual machine space.

Re:Beaowulf not the target audience

[Doktor Memory]

now you could get 8 processors of RS/6000 goodness, run production on 4 processors, Test on 2 processors, and Dev on 2 processors.

What you're suggesting is pretty much the opposite of how this package works. As the author himself states, you cannot dedicate hardware resources to a vserver. Only one kernel is ever running, and you use all of your cpus or none. Process- and user-space isolation is provided, but if a process in one vserver tickles a kernel bug that crashes the system, the whole ball of wax will come down with that vserver. (Likewise, it's very likely that a kernel-level root exploit will allow you to break out of the vserver and attack the whole system.)

Essentially, vserver is to the process space what chroot is to the filesystem layer.

This is not inherantly better or worse than the "system partitioning" approach; it's just a different approach, and will have different uses.

mosix

[morcheeba]

I wonder how this would work with mosix... it could be a dream system!

You could use mosix to combine the compute resources of several boxes to look like one box. And then, you could use this divy up the space so that people don't step on each other. When anyone (working in thier own space) kicks off a large compile, the load would transparently be distributed among all the boxen.

Of course, I have zippy experience with any of this, but it sounds possible.