Debian: What an OS

Well the topic says it all. I have switched to debian gnu/linux and my engineering skills were tested. I faced troubles at almost every stage after installation. Let me describe the process.

I got myself a debian cd, put it in the cd - drive, restarted my laptop and after hitting the enter key about 10 times, debian was installed. I was greeted by a not-so-good-looking screen (clearlooks theme + gnome icon theme). I fired up iceweasel (debian's patched version of firefox (they are not allowed to call it firefox)). Within 5 minutes, my fan begins spinning. I realise that I am just running a web browser and reading a BOFH story. I check the output of cat /proc/acpi/thermal_zone/THRM/temperature. The output is 72 Degrees C. I am stunned. I close all applications and leave my laptop alone. Five minutes later, my laptop's fan is still spinning. I realize that something is surely wrong. I devise a plan. My first stop is to check how the fan's trip points. Trip points are basically the temperatures at which the behaviour or the system or the fan changes. I checked the output of "cat /proc/acpi/thermal_zone/THRM/trip_points". The output was:

critical (S5):           100 C
passive:                 92 C: tc1=2 tc2=3 tsp=100 devices=0xc124657c
active[0]:               73 C: devices=0xc12525a4
active[1]:               66 C: devices=0xc1252694

So there you go. My fan would begin spinning when the cpu temperature hits 66 C. I decide to change the values a bit. I decide that it would be better if I set the values at boot-time and I add the following line to /etc/init.d/

echo 90:0:62:52:50 > /proc/acpi/thermal_zone/THRM/trip_points

Upon booting, I check the trip points and I get:

critical (S5):           90 C
passive:                 62 C: tc1=2 tc2=3 tsp=100 devices=0xc124657c
active[0]:               52 C: devices=0xc12525a4
active[1]:               50 C: devices=0xc1252694

It works! But just a few seconds later, the fan begins to spin. I check the temp again and: 63 C. "!@$@!#". What the bloody hell. The temperature kept shooting up and stayed put at 70 C. I shut my laptop down and open it up and armed with a cotton swab, I aim to clean up the buge amount of dust on the fan. Bad luck, there isn't any significant amount of dust there to cause a huge problem. I then realise that this route won't lead to a solution as well. I finally reboot my laptop with the aim of planning my next move. I run:

cat /proc/cpuinfo

The output ensues and line 7 catches my eye:

cpu MHz:                                            1600

Bingo ! My genius brain figures out that cpu scaling is disabled. My cpu was running at 1600 MHz irrespective of the apps running. I know quite a bit about scaling as I had once asked people on IRC for help on overclocking my cpu. I was pointed to a tutorial about scaling then. I installed cpufrequtils and did:

modprobe acpi-cpufreq
/etc/init.d/cpufrequtils restart

Thats all.
There is one issue however. While booting, debian complains that the OnDemand CPU failed. I was a bit irritated by this. But it was easy to figure out the solution. Plainly add modprobe acpi-cpufreq to /etc/init.d/cpufrequtils.
Thats all!

2 responses to “Debian: What an OS”

  1. Kalyani

    Hi. I Googled Edubuntu and Hyderabad and your blog showed up...

    I am an educator planning to set up an after-school activity centre for school children. A computer lab is part of my plan.

    I am thinking of Edubuntu with a 8 thin-client lab. I've seen a mention of your plans to work on promoting Edubuntu in Hyderabad schools... I could use some help and advice...

    I was wondering if you know of anyone who did an Edubuntu lab with 8 or more thin clients in Hyderabad? Seeing a lab in operation will help to clarify my hard ware specifications.

  2. shriphani

    I don't know of any such lab. I can give you the hardware specs though. a p2 with 64 MB RAM will work as a thin client and 150 MB of RAM per client on the server should suffice. Remember that server needs to be quite powerful. Intel Xeon prolly :)

Leave a Reply