Category Archives: debian

Debian freezes randomly

Since about one year I own a ultrabook ‘Wortmann Terra Mobile 1450 II’ which I run on Linux.  The system contains a Intel Core i7-351U chip set and 8GB RAM. But this system shows a very strange problem on Linux (and as I guess maybe also on other operating systems): randomly the system freezes.

When the system freezes no mouse , no keyboard, no REISUB was possible. The screen is corrupted and did not update. The only key board functionality which is still possible is Fn+F9 (switch display on/off). So the only possibility was to to switch off the system hard.

The freeze occurs when the system runs on battery as also when it is plugged. It looked as if the errors occurs more frequently at high memory usage.

The memory…

A memory check (with memtest86+) indicates no problem. Therefore, I thought it had to do something with the kernel. See also the discussion here. But updating every week a new kernel version and playing around with several kernel boot options the problem still occurs.

Back to the idea that the problem comes from the RAM I installed the tool ‘memtester’. With this tool you can test memory when linux is running. For Example I started a test to check 7GB RAM with the following command:

memtester 7G 1

And now I was able to force the freeze. During such a test each time my system freezes. Also when I booted in kernel recovery mode the same situation – system freezes! So this indicated to me that the problem is with the memory.

The solution

If the memory seems to be ok in general (memtest86+ indicates no errors) but the system freezes in situations with heavy  memory usage (memtester) then it may have something to do with overclocking the memory?

In my BIOS settings () I found the following setting:

->Chipset
-> System Agent (SA) Configuration
-> Memory Configuration
-> Memory Frequency Limiter

This was defined as ‘AUTO’. What ever this means I changed the value to lowest available setting of ‘1067’ (other values where 1600, 1867, … up to 2667). With this setting I can not see any substantial impairment of the speed. But from now on my system runs without any more freezes!

So if you are also faced with the problem of random freezes, first try to control the overclocking of your memory. I hope this will help you too.

After all the last question is: Is my hardware to fast for linux or is linux to fast for my hardware 😉

 

Eclipse crashes in Debian Jessie

After some updates in my Debian/Jessie installation I run into a strange problem with Eclipse. When I start Eclipse first everything looks fine, but in the moment I use some type-ahead features or browsing classes or methods in a java-file Eclipse crashes without any error message. Maybe the problem is related to an update in libwebkitgtk-3.0.

After some searching I was finally able to fix the problem by adding the following line to my eclipse.ini:

-Dorg.eclipse.swt.browser.DefaultType=mozilla

See also this bug report:
https://bugs.eclipse.org/bugs/show_bug.cgi?id=334466

‘evbug’ auf die Blacklist setzen

Ich hatte das Problem das mein kern.log file mit Meldungen dieser Art geflutet wurde:

Sep 27 18:07:48 r-ultrabook kernel: [ 380.012332] evbug: Event. Dev: input6, Type: 0, Code: 0, Value: 0
Sep 27 18:07:48 r-ultrabook kernel: [ 380.028334] evbug: Event. Dev: input6, Type: 2, Code: 1, Value: -1
Sep 27 18:07:48 r-ultrabook kernel: [ 380.028343] evbug: Event. Dev: input6, Type: 0, Code: 0, Value: 0
Sep 27 18:07:48 r-ultrabook kernel: [ 380.044419] evbug: Event. Dev: input6, Type: 2, Code: 1, Value: -1
Sep 27 18:07:48 r-ultrabook kernel: [ 380.044430] evbug: Event. Dev: input6, Type: 0, Code: 0, Value: 0

Diese Meldungen werden wohl vom Modul  ‘evbug’ erzeugt und dienen als Debug Information. Das Modul sollte im Normalfall eigentlicht im Kernel geladen werden.

Um nun das Modul abzuschalten kann man es auf die blacklist setzen.

Dazu habe ich die (bei mir noch nicht vorhandene) Datei /etc/modprobe.d/blacklist.conf erstellt und folgenden Inhalt eingetragen:

# This file lists those modules which we don't want to be loaded by
# alias expansion, usually so some other driver will be loaded for the
# device instead.
# evbug is a debug tool that should be loaded explicitly
blacklist evbug

Dies führt dazu das das Modul beim nächsten booten nicht mehr geladen wird und die Meldungen verschwinden.

Debian – systemd

Debian Weezy verwendet in der aktuellen version immer noch den Init-Deamon System-V-init. Dieser kann durch den neueren deamon systemd ersetzt werden. Dieser erlaubt einen schnelleren  Bootvorgang, da beim booten mehrere dienste parallel gestartet werden können:

# apt-get update
# apt-get install systemd