Ubuntu 10.04 (Lucid Lynx) features new panel applets called “indicator applets”. If you want to get rid of some of them, they can be removed by removing the corresponding package(s) using your favourite tool (Synaptic, aptitude, apt-get, …): indicator-me provides the menu with your avatar and your availability status indicator-messages provides the menu for email/Evolution, […]
Author Archives: tiwoc
List of Publications / Bachelor Thesis
I just added a page featuring my (currently quite short) list of publications.
Automated MySQL backup for shared webhosting
What to do if you want to use mysqldump in a shared hosting environment without being able to access the shell (SSH…)? Use a Perl CGI script: #!/usr/bin/perl -w use strict; use CGI::Carp qw(fatalsToBrowser); print “Content-type: text/plain\nContent-disposition: attachment; filename=\”db_backup.sql\”\n\n”; print qx(mysqldump -uUSERNAME -pPASSWORD DATABASE 2>&1); Replace USERNAME, PASSWORD and DATABASE with the configuration data for […]
Dell Preboot Authentication: Deleting smartcard associations
Laptops from the new Dell Latitude E series come with an OEM version of Wave Embassy Trust Suite. This software can be used (amongst others) for configuring BIOS and hard disk “passwords” based on smartcard authentication. This is a nice feature, but what if you try to turn this off again after trying it out? […]
ionice: Controlling the Linux I/O scheduler
Linux is quite good at scheduling the CPU time of running programs: Even when a process is running which constantly uses up all processor power, it is still possible to use another (interactive) program nearly as fast as on an idle system. But if a process is doing heavy I/O operations (i.e. backup software), the […]
Clean MySQL backup using mysqldump
If you need to configure a backup of a MySQL database server, you shouldn’t simply copy it’s database files from /var/lib/mysql since they might be inconsistent (due to simultaneous changes). mysqldump is a safe choice for this task. I wrote a simple script for Debian that uses the pre-configured “debian-sys-maint” account and compresses the output: […]
java -jar ignores classpath — Workaround
When you want to run a Java class wich needs additional libraries, you usually run java -cp mylib.jar MyClass or you specify the environment variable $CLASSPATH before running the class. When you have a JAR file you want to run, you usually do this by issuing java -jar myjarfile.jar Maybe you’ll think: Hey, I want […]
Strato V-Server/Virtuozzo: Memory usage
This blog runs on a virtual server offered by Strato. They use Virtuozzo for virtualization which has a drawback: If you use top, free or other tools to show the current memory usage, not only your “slice” of the machine but more (all?) of the memory is measured. This doesn’t help much if you try […]
Kundenfreundlichkeit vs. Shareholder Value
Gunter Dueck ist Mathematikprofessor und arbeitet als “Distinguished Engineer” bei IBM. Er veröffentlicht regelmäßig (aber nicht täglich…) seine Kolumne “Daily Dueck”, in der er über Wirtschaft und Arbeitsleben philosophiert. Heute schreibt er über “Kunde und Überkunde”. Sehr lesenswert!
Caching using weak references
Some time ago I wrote a Java class that caches generated images so I don’t need to re-render them all the time (rendering SVG graphics takes some time…). There’s only one problem: As more and more different images are getting cached, the maximum heap space of the JVM will eventually get exhausted. Increasing this limit […]