Posts Tagged ‘java’


Xen Summit Fall 2007

November 20, 2007

I was hoping for the material to be available already so I could link to it, but it is not yet the case.

So what is in store for Xen?

As I mentioned previously for day one some directions on Xen roadmap were shown some interesting xen extensions were shown, one I found particularly interesting is JavaGuest (Java running on top of Xen, allowing a full Java stack… more on that in a post to follow).

Day 2 started with AMD and Intel updates, and as I said it is really great that they are caring about virtualization. I am particularly excited about the features coming up with Intel VT-d which allows DMA for IO devices by means of DMA remapping (basically assigning regions of host physical memory as “protection domains”, assigning devices to this domains and remapping DMA access to host physical addresses on this domains, the remapping being done in HW).

Also very interesting was Samsung’s presentation on the ARM port of Xen, which they showed originally on the previous Xen Summit. Now it is even more advanced, they even showed Doom running in one of the domains, and following the current trend of disaggregating Dom0, they have a separate domain for drivers. Very good work, I really hope they release their work, there are a lot of great things that can be done with it.

Very interesting work for consolidating memory in Xen (the more VMs you run the more important this will become) by using Copy on Write was also shown, and a great approach at treating Xen VM as transactional applications (checkpointing the VM every few milliseconds, executing speculatively and holding any output in between checkpoints).

Finally, the recently announced OracleVM (Sun, Novell and RedHat also showed their stuff), now that Viridian is going to be released soon, pretty much all the major players have a virtualization solution in hand, this is definitely getting big.


Android SDK released

November 13, 2007

Yeah… another android post. Probably not many more news after this one though.

Anyway, the SDK was finally released, and it turns out that it is just a bunch of Java classes (yeah… I am a bit disappointed).

I agree it has many innovative and cool features, all applications are first class (so you can override any aspect of your phone), and the API seems to be nice, particularly the UI part (I haven’t gone very deep but I like what I saw) and the potential ease of use in general… but still it is no more than a bunch of optimized classes for a modified Java VM!

What if you don’t like / don’t know Java? What if your applications are currently in C/C++, Python, Perl, name_your_favorite? I wonder if this is more about Google’s powerful name than anything else. Furthermore what happens to write once run anywhere if you use a non-standard non-JCP JVM? I don’t think this is necessarily good for Java (actually it may be quite bad), and all the Symbian, Windows Mobile and Mac OSX phones are not just going to disappear (and more unlikely to support Dalvik)

We have Qtopia, we have Maemo, is really this Java VM thing a reason good enough to justify yet another Linux for phones? I have to admit that I am also disappointed because I was hoping to see virtualization being used in some other context.