After my post about capturing full page screenshots with firefox I started wondering if there was a way to do screencasts using Linux. It just so happens that you can. There are a couple different options if you want a pure movie of your desktop but I was more interested in a flash version. I found what I was looking for with this tutorial on how to record videos of your desktop that uses vnc2swf.
I've put together another 5 ImageMagick command line examples as a followup to part 1. These examples are a little more advanced and include some extra information on techniques.
Sometimes I curse the day I decided to get a 64 bit box. Everything is fine until I want to build something by hand or upgrade something and then if it doesn't just work it is like a maze of problems.
Recently I was trying to build firefox from source along with XULRunner so that I could try out JavaXPCOM. The first problem I ran into was a GCC 4 bug that breaks the build. Luckily someone out there had an easy fix for the problem (see GCC4.0 – relocation R_X86_64_PC32 against memcpy@@GLIBC_2.2.5 can not be used). After getting that problem fixed an a little fight with setting up XULRunner I got a very simple program working. That is when the 2nd problem showed up. When I tried to use some of the GUI functions I started getting core dumps from within GTK2. At that point I gave up and moved to my laptop. The same code worked right off using my laptop.
I should have instructions soon on how to embed gecko into a java app with JavaXPCOM. There isn't much documentation or example code out there on making it work. As for the 64 bit box, I think I have had about as much of it as I can take. At least it can run in 32 bit mode when I decide to re-install.
On a number of occasions I've used RRDTool to graph network traffic and the like. A few years ago when I started using cacti I started wondering how to make the graphs myself. Creating the graphs on the command line isn't that hard once you know how to set things up and it turns out doing the same in PHP is just as easy.
Vitamin has a good article today on the importance of maintainable javascript. 95% of what the article covers is applicable to any code. The important parts of the article cover javascript specific things like: object literals, namespaces and where to go when you want to compress your javascript to save bandwidth/make it download faster. They recommend packer and JSMIN as two javascript compressors but I think JSMIN is probably a better bet mainly because you can run it from the command line and make it part of a build script.
If you have ever wanted to manipulate images under linux you probably have used Gimp. This isn't your only option and if you want to do things from the command line a better option is to use ImageMagick's convert utility.
I've put together 5 simple command line examples that I have found useful. This is just a sample of what you can do with convert. To see more examples and get more explanation of options see: ImageMagick v6 Examples.
I found a post about an alternative approach to tagging today and thought it would be interesting if someone made a wordpress plugin that would use this idea. It seems like it might be a nice alternative to the normal site map that most sites have when there is a lot of information to drill down into.
I was reading an article today that asks the question Are Tape Backup systems obsolete? I would say the answer is yes and that it has been that way for some time now.
Take google who build thier own commodity hardware. How would they ever back up so much data? Why would they even try? It would be much easier to just do what they are doing and replicate the data multiple places. Drives are becoming so huge how can you manage to keep up with your tape library solution? What if you had to back up the Sun Thumper at 24T? That would require a massive number of tapes.
We tried to use tapes for the longest time but the expense got to be too much. We were adding hardware left and right with drives that could fill an entire tape. After looking at autoloaders to cover the amount of data our graphics developers produce we gave up on tapes. That was two years ago. We went with Amanda's tapeless setup and a load of cheap hard drives that we could swap out for offsite backups. This setup has worked great. The cheap drives let us to expand our backup range from a couple weeks to month and longer if we wanted to. Having the extra space gave us the ability to back up user pcs if we needed to as well. As the size of drives for servers we buy increases so does are ability to expand our backup system. Moving to a hard drive based backup scheme has releaved us of the burden of waiting for tapes to catch up which they never seem to do.
backup, amanda, tape
This is one large set of disks to have in only 4u of space. And to top it off the thing has 4 cores. I love commodity hardware and sun has been rolling out some nice commodity hardware these days. The price for some of the equipment has started to catch my eye now. I think as far as initial interest this file server would be great if they just had ZFS working for linux. It looks like they are trying to port it with FUSE as a Google SOC project. If they get it going it would probably fit in well with XEN.