Semantic Web
by David Kowis on Feb.03, 2010, under Coding!, Gripes, Java
At work I’m dealing with this “Semantic Web” concept thingy. “Web 3.0″ it is called. Frankly I don’t see the point in it yet. The goal is to have the internet also contain data to ensure that computers can find relations in the data and such, not just pages with links that people can browse. One of our projects involves taking unstructured data and mining entities and relationships from it. I’ve picked up a book, the only book, on programming software to (ab)use the semantic web. So far, I am unimpressed. The source code in the book does not match the source code that you can download from the books website. And, the two different packages on the books website (one is just Chapter 2’s code, the other is all the code for the whole book) also had different code, and the “all encompassing” one was even missing the right files needed to run the code!
So yeah, unimpressed.
Xen 4.0 Comin down the Pike!
by David Kowis on Dec.07, 2009, under Linux
http://blog.xen.org/index.php/2009/12/02/xen-4-0-release-information/
It would appear that Xen 4.0 is due out Q1 2010. That’s not very far off. I will perhaps wait on redoing my Xen network setup until that time. I need to get it working better. I’ve been having problems suspending VMs. Supposedly this is due to the guest kernel not behaving nicely. Patches have been submitted upstream from what I’ve been told and the pull request has been made to Linus to pull it into the kernel.
There’s lots of good stuff coming in Xen 4.0 too. Remus is particularly interesting. I will have to experiment with that. Live failover of boxes. I don’t know what I’d do with that to be honest. I guess you could set up two physical boxes, with the same virtual machines on them, and have 100% uptime, well like 9 9’s of uptime. (Assuming no stupid admin errors.)
Groovy Threading and Java Threading
by David Kowis on Nov.30, 2009, under Coding!, Groovy
I must be doing something wrong regarding my groovy code. I was talking to a friend and fiddling with a tower of hanoi solver code. Just burns in CPU basically. Now I hacked it up in groovy, after he talked about it, just because. Well I came up with a groovy-ish solution that should do the same thing his java code did. However, the Java code actually ran like 8 threads, whereas my groovy code only ran about 3. Based entirely on CPU usage in linux. On the same box. I don’t understand… The code follows. (continue reading…)
Fedora 12 Xen RPMs
by David Kowis on Nov.17, 2009, under Linux, fedora
I built these on a recently updated Fedora 12 box. I haven’t yet had an opportunity to test them. If you do use them and they work great, or not, post in the comments please.
Xen 3.4.2 rpms for Fedora 11 x86_64
by David Kowis on Nov.12, 2009, under Linux, W00t!, fedora
I was using xen 3.4.1 on my fedora 11 Domain0, but I couldn’t ever suspend anything. xm save always failed. Someone on IRC suggested that it was the guest kernel that was to blame. Turns out it was xen 3.4.1.
After many hours searching the intertubes for a srpm or a spec file for building xen 3.4.2 for fedora, I decided that I would hack an existing one to 3.4.2 and hope for the best.
It built after I removed a few patches. The patches mostly complained about being already applied, so I assume the bugs the patches were addressing were fixed in 3.4.2. I have generated rpms for x86_64 and put the spec file up on my site. Enjoy.
