Minn Myat Soe :: His Notes

I always like to play around with new distros that I can find from distrowatch.com. Gentoo being my primary distribution, I have Arch as my second distribution. Arch also offers the flexible system. Almost every linux systems are the same in functionality and the features, and from as far as I can see, the only difference arethat how they implement the front-ends, and how they manage the packages.

With Gentoo, I am not being fancied by easy or pretty front-ends (you can say Gentoo text output is quite colorful), but I’m more interested in how to add/remove/update new software package onto the system. I don’t think anyone will content with the packages that comes with the distro. Package Management offers various ways to install/remove the software as well as update one package or the whole system. It also allows us to select software repositories which we download the packages from. These are some package management systems that usually tied to a distro and its variants:

apt-get for Debian, Ubuntu, etc.
emerge for Gentoo, Sabayon
yum for Fedora, etc.

For more information about the package management systems for linux distributions, you can always refer to those good documents:

• <http://www.enterprisenetworkingplanet.com/netos/article.php/3665371>
• <http://distrowatch.com/weekly.php?issue=20080922>

I’m setting up another Gentoo on my office desktop.

My compiler on Gentoo stops at this error when compiling certain packages. I just noticed that as I tried to install binary drivers for ATI card (X1300).

I tried to re-emerge GCC, but it didn’t help. But finally I noticed the cause as I searched through the forum and the net.

It’s because of the missing symbolic to libGL.so in /usr/src.

I was using ATI drivers for OpenGL so my Gentoo symbolically linked to that library. “dri” was not working so I tried to downgrade the driver to lower version by uninstalling it. But when I did a re-install, compiler stopped there, saying it “Cannot find -lGl”.

Actually what I should have done is to switch the OpenGL library to Xorg libraries before uninstalling the ATI drivers.

Now I’m able to compile the ATI drivers, but still “dri” is not working. I need to figure it out.

Gentoo does really have Eclipse SDK in its portage. I once used it a long time ago and I gave up soon after I learned that it’s more difficult to update the portage version of Eclipse (at least to me).

Now I decided to install Eclipse Europa, and grabbed myself a Gtk version of Europa and extracted in /opt.

When when /opt/eclipse/eclipse was started, Eclipse stopped the execution, giving me the following error message.

 JVM terminated. Exit code=1/usr/bin/run-java-tool
-Xms40m
-Xmx256m
-Dosgi.bundlefile.limit=100
-jar /opt/eclipse/plugins/org.eclipse.equinox.launcher_1.0.0.v20070606.jar
-os linux
-ws gtk
-arch x86
-showsplash
-launcher /opt/eclipse/eclipse
-name Eclipse
--launcher.library /opt/eclipse/plugins/org.eclipse.equinox.launcher.gtk.linux.x86_1.0.0.v20070606/eclipse_1017a.so
-startup /opt/eclipse/plugins/org.eclipse.equinox.launcher_1.0.0.v20070606.jar
-exitdata d5801b
-vm /usr/bin/run-java-tool
-vmargs
-Xms40m
-Xmx256m
-Dosgi.bundlefile.limit=100
-jar /opt/eclipse/plugins/org.eclipse.equinox.launcher_1.0.0.v20070606.jar

It seemed like vanilla Eclipse didn’t really want to work with Gentoo’s Java environment.

So I added a path to Java VM when starting Eclipse, and it began to work.

./eclipse -vm `java-config-2 --java`

It was because eclipse was running Gentoo’s run-java-tool instead of java, and this made $tool variable in line 15 of run-java-tool to become “run-java-tool” instead of “java”. Then it leads to wrong interpretation of JVM path.

It can also be fixed by adding

[[ $tool = "run-java-tool" ]] && tool="java"

(replace & with actual ampersand symbol)
after line 15,

tool=$(basname $O)

Or alternatively, you can directly call Equinox (Eclipse Launcher) by using the examples described in Eclipse Wiki. Here’s the sample bash script:

#!/bin/bash# set path to eclipse folder. If local folder, use '.'; otherwise, use /path/to/eclipse/
eclipsehome=".";
# get path to equinox jar inside $eclipsehome folder
cp=$(find <em>$eclipsehome</em> -name "org.eclipse.equinox.launcher_*.jar" | sort | tail -1);
# start Eclipse w/ java
/opt/java50/bin/java -cp $cp org.eclipse.equinox.launcher.Main ...

I just found an article titled “Myanmar Insights”, on a blog. The author seems to be a singaporean. Here are some of his comments:

• most people sarongs (both men and women)
• costs US$1500 to own a sim card (excluding mobile phone and calling charges)
• limited imported cars; all mainly recycled & non-aircon
• The buses are like lorries which ferried many
• Myanmar uses two currencies; US and kyats (they’ve 2 exchange rates – official vs black mkt)
• There are 3 seasons (dry & hot, wet & hot, dry & less hot – unfortunately we went in the hottest season
• Yahoo, hotmail & gmail are prohibited
• Women use grinded tree bark on their faces as a form or sunscreen/ makeup (see below)
• Many speak English, and they are known to be hardworking people
• School fees costs US$1/ month in one of the unis
• Blackouts are a way of life
• Many children run along roads with a baby in hand to ask for money
• Precious stones/ gems are one of the natural resources (incl sapphire, jade, emerald, etc)

And finally his conclusion:

on a last note, this trips highlights the contrast of lifestyles in singapore vs myanmar…which appears stark to me. and i hope many of us (including myself) dont have to lose it to appreciate our country (govt setup, infrastructure, etc)

Despite these comments, there are people who did enjoy travelling to Myanmar =)

My kernel has been upgraded to 2.6.21. The sound card driver provided by my previous kernel 2.6.18 did not properly support my sound card, and I had to use alsa-driver sound modules. Now I have compiled the driver that comes with 2.6.21 into the new kernel, and it works perfectly.

I also decided to give my kernel a new scheduler, too. It’s Completely Fair Scheduler (CFS) v15, developed by Ingo Molnar from Red Hat. It promises to fix deficiencies of vanilla scheduler. We might have already experienced Windows NT scheduling. At least we may have configured our computers’ role as workstation or server in Windows XP. And there are some interesting links that will give us a basic idea about linux process scheduling. These include:

• Process Scheduling (O’Reilly Understanding Linux Kernels)
• Linux Kernel in a Nutshell (O’Reilly, and it’s for kernel 2.6.18 :)
• Inside the Linux Scheduler (IBM DeveloperWorks)

The O(1) scheduler in 2.6 kernel written by Ingo Molnar from Red Hat is a complete improvement over 2.4′s scheduler. Being O(1), it takes the same amount of time to select the best task from the runnable processes. CFS is the completely rewrite of O(1) scheduler.

In addition to CFS patch, I also applied regular gentoo patchset, Con Kolivas patchset and suspend2 patchset.

One day, I will give Con Kolivas’ Staircase Deadline (SD) scheduler a try, and feel the difference between SD and CFS. These two schedulers are being vigorously tested by Linux developers, and in the end one of them is likely to be accepted into mainline.

Finally, I have to re-compile fuse driver for ntfs-3g after compiling new kernel. I will definitely patch for fuse in my kernel when I upgrade to next version