Friday May 30, 2008

So long and thanks for all the fish ...

After 13 years at Sun, it's time to move on.

Sadly, today is my final day, and my last blog entry here (at least for a while).

If you're still looking to track me down, you might start at my personal website It's not much at the moment, but who knows what may happen in the future.

To the Sun colleagues I leave behind; farewell - I'll miss you!



Thursday May 29, 2008

New hypervisor API specification released

The API specification for Logical Domains (and the SPARC hypervisor) is now available for download at It's a one-stop shop for your virtual OS programming needs.

I'm hoping we'll move the document to a more accessible location on the web-site, so just in case that happens and the link above ceases to work, a local copy is also available.

This document provides an overview of how the whole virtualization environment hangs together, followed by detailed descriptions of each of the interfaces available to an operating system running in a virtual machine ("Logical Domain"). This includes virtual devices such as disk and networking.

If you're serious about hacking a kernel for a sun4v UltraSPARC machine, be it Linux, FreeBSD or OpenSolaris, or even if your just curious you'll wan to take a look at this.

Tuesday Aug 07, 2007

Linux & Solaris booting together

Since I'm in the mood for capturing flash demos, I thought one more might be interesting:

First we start with Ubuntu Linux booting and running in a Logical Domain. You can see that CPU DR is also implemented so the OS can cope with dynamically adding and removing CPUs from the domain without having to reboot first.

Then just for kicks and grins, I create another guest domain - this time running Solaris 10 - Just to prove that you really can run different Operating Systems on the same chip in separate domains. (btw: this also shows both Solaris and Linux booting in parallel in a race to the login: prompt).

My thanks to David Miller and Fabbio Massimo for rolling the Linux disk image, and Alex and Narayan for helping with the installation.

64 domain capable (UltraSPARC-T2) chip launched today

(There's a flash demo in here - so read on)

Today Sun launched the UltraSPARC-T2 processor.

This is the second generation in the Niagara processor family, and comes with twice as many processing strands, more cache, more memory bandwidth - and an amazing two 10Gb/s ethernet interfaces plumbed right into the heart of the on-chip memory system.

Of course this processor supports LDoms from the get-go, and the first systems will be delivered with LDoms technology.

With this generation of processor you can create and run up to 64 logical domains each with its own Operating System instance - by the way - this isn't just marketing fluff, you really can, and to prove the point click here for a demo of 64 domains booting and running on a UltraSPARC-T2 system.

Be warned this is a large - as in 1600x1200 pixel - flash animation). If your screen is pixel challenged, a 800x600 shrunk version is available here.

Monday Aug 06, 2007

Linux in a LDom

I'm way late in posting this (been buried in other stuff recently), but in case you haven't heard David Miller and Fabio Massimo have Linux up and running in a LDoms guest using virtual devices.

Congratulations to Dave and Fabio on a truly stellar (no pun intended) job!

Dave's announcement is on his blog page here.

Thursday May 10, 2007

On the sun4v architecture ...

I was talking with one of my colleagues yesterday about OpenSPARC, and this reminded me about a presentation I gave over a year ago at the 2006 Multi-core expo about the changes we made to the SPARC architecture in order to support a full virtual machine environment. That talk was updated as a tutorial for the ASPLOS XII conference last year.

Since I'll probably be re-using a number of these slides in later blog entries, I thought it might be of interest to dig up the original PDF version and put that online first. The full slide deck can be found here:

domaining slide

... and they can also be found together with other tutorials on OpenSPARC.

Tuesday May 01, 2007

LDoms 1.0 product page

The LDoms product page is now live.

More info and details about this product are coming.

Oh yes and it's free !

Thursday Apr 26, 2007

LDoms 1.0 is released !

Version 1.0 of Sun's Logical Domains product is now released!

If you own (or have access to) a UltraSPARC-T1 (aka "Niagara") processor based machine this is for you. If you don't have one go here.

You can find all the relevant bits on the download page, and it is free.

Up to 32 separate virtual machines - each with its own OS instance running on a single cool threads chip. For a demo click here!

The product is delivered as a firmware upgrade for your platform that includes the domaining capable Hypervisor as well as updates to the service processor. In addition there are updates for Solaris 10, including the domain manager package that configures and manages your platform's virtual machines.

Thursday Apr 19, 2007

Getting started

My name is Ashley Saulsbury, and I've finally been tagged (guilted) into starting a Sun weblog.

So, without further ado;

I'm a Distinguished Engineer here at Sun, and I am the architect for Sun's Logical Domaining ("LDom") technology - about which I'll be blogging in future entries.

In May I'll have been at Sun 12 years - working on a diverse range of things, from streaming hours of uncompressed digital IMAX resolution movies onto 20' screens, to blasting high energy neutron beams at microprocessors.

The last six years though have been spent (mostly) developing the (sun4v) virtualisation architecture for SPARC, it's delivery with UltraSPARC-T1, and the now publically available Logical Domaining technology that lets you run 10s (and soon to be 100s) of virtual machines on a single box.

I expect to be talking a lot more about this work in forthcoming entries, so if you're interested in the topic do watch this space, and by all means post comments. If I ever get around to writing any non-work related blog entries you'll likely find them at





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