I was initially going to just do a writeup on this blog, but I asked the folks at LWN if they were interested.. and they were! This is my first article for LWN. I’ve followed the site and the excellent content for a really long time, and now I’m very thrilled to also be an author.
We recently celebrated 25 years of Linux on the 25th anniversary of the famous email Linus sent to announce the start of the Linux project. Going by the same yardstick, today marks the 10th anniversary of the KVM project — Avi Kivity first announced the project on the 19th Oct, 2006 by this posting on LKML:
The first patchset added support for hardware virtualization on Linux for the Intel CPUs. Support for AMD CPUs followed soon:
KVM was subsequently merged in the upstream kernel on the 10th December 2006 (commit 6aa8b732ca01c3d7a54e93f4d701b8aabbe60fb7). Linux 2.6.20, released on 4 Feb 2007 was the first kernel release to include KVM.
KVM has come a long way in these 10 years. I’m writing a detailed post about some of the history of the KVM project — stay tuned for that. [Update 3 Nov 2016: I’ve written that article now at LWN.net: https://lwn.net/Articles/705160/]
Till then, cheers!
I did a talk earlier today at the wonderful venue of the Science Centre Singapore at FOSSASIA 2016, titled ‘Virtualization and Containers.’ Over the last few years, several “cool new” and “next big thing” technologies have been introduced to the world, and these buzzwords leave people all dazed and confused.
One of my aims for this talk was to introduce people to the concepts behind virtualization and containers, explain that these aren’t really new technologies, and why there’s so much interest in them of late.
I also think there’s a lot of misinformation spread around these topics, so this was also an attempt to set some facts straight.
The slides are here, and I will post an update with the link to the video.
Edit: video is up.
I just did a talk titled ‘Live Migration of Virtual Machines From The Bottom Up‘ at the FOSDEM conference in Brussels, Belgium. The slides are available at this location.
The talk introduced the KVM stack (Linux, KVM, QEMU, libvirt) and live migration; introduced ways the higher layers (especially oVirt and OpenStack) use KVM and migration, and what challenges the KVM team faces in working with varying use-cases and new features added to make migration work, and work faster.
There was a video recording, I will post the link to it in a separate post.
Update: video recording available at this location.
QEMU is the software that creates virtual hardware which guest operating systems run on top of. All (well, almost all — see note below[*]) the hardware that a guest OS has access to is actually written to some specifications in software — i.e. no physical hardware is involved. For the QEMU/KVM hypervisor, most of these devices are written in the QEMU source repository. A few devices are part of the KVM code in the Linux kernel. QEMU also handles a lot of host-specific stuff, like storage and networking for the virtual machines.
[* Exception: physical hardware devices assigned to guests.]
Many contributors to the QEMU and KVM projects meet at the annual KVM Forum conference to talk about new features, new developments, what changed since the last conference, etc.
The QEMU project released version 2.4 just a week before the 2015 edition of KVM Forum. I thought that was a good opportunity to gather a few developers and maintainers, and get them on video where we can see them speak about the improvements they made in the 2.4 release, and what we can expect in the 2.5 release.
I’ve written previously about random numbers in virtual machines. KVM still remains the only hypervisor to offer an RNG device to guests.
Quite a lot of exciting changes have landed in the upstream Linux kernel since that last post. I have written an article in the RHEL blog about it: Red Hat Enterprise Linux Virtual Machines: Access to Random Numbers Made Easy.
That articles talks about the improvements in the recent RHEL 7.1 release. In upstream terms, all the changes written about have landed in kernel 3.17; so Fedora 21 out-of-the-box, and Fedora 20 after updates, have benefited from the additions.
All the benefits listed in the article apply to all Linux guest VMs running under KVM if they have the virtio-rng device enabled, and run kernel 3.17+ in the guest.
When the call for bids for FUDCon APAC 2015 was put out, a few of us huddled together to discuss a bid from India. We had already organised a successful FUDCon in Pune in 2011, so our initial conversations were around which city to host it in. Pune won again, just because the number of volunteers available in Pune are more than any other place in India, and Pune has several technical colleges, which makes hosting the event at one of them easier.
This time around, we’re proposing to host the FUDCon at the MITCOE campus, more details in the bid page.
I spoke at the CentOS Dojo in Pune yesterday on new features available in CentOS release 7.0 since the 6 release. Slides are available here: What’s New in Virtualization. The event was organized by the Pune GNU/Linux Users Group (PLUG) for the CentOS project.
It’s been a couple of weeks that I’ve returned from Düsseldorf, Germany, after attending the seventh KVM Forum; an event where developers and users of the Linux virtualization technology gather to discuss the state of the hypervisor and tools around it, and brainstorm on future plans. As with the previous few years, the event was co-located with LinuxCon Europe.
A few observations from the event, in random order:
The 2014 edition of KVM Forum is less than a week away. The schedule of the talks is available at this location. Use this link to add the schedule to your calendar. A few slides have already been uploaded for some of the talks.
As with last year, we’ll live-stream and record all talks, keep an eye on the wiki page for details.
One notable observation about the schedule is that it’s much relaxed from the last few years, and there are far fewer talks in parallel this time around. There’s a lot of time for interaction / networking / socializing. If you’re in Dusseldorf next week, please come by and say ‘hello!’