Jan 27, 2015

Maven indexing in Netbeans filled up my /tmp and therefore the RAM/SWAP of my Linuxbox.

NetBeans can be configured to index maven repositories.



During the index phase the data is stored in a temp. directory, which was
on my Fedora box in /tmp/nexus...

This got very huge and used a whole lot of memory which increased the
SWAP usage.

To prevent the usage, I redirected the java tmp directory in
<netbeans>/etc/netbeans.conf by using the start parameter:

-J-Djava.io.tmpdir=/var/tmp
 
 
and set the tmpdir to /var/tmp and after this the memory pressure  is gone.

Jan 22, 2015

docker container could not start on Fedora 21 because of failing to write the memory limits

Today I restarted my Fedora 21 after updates. But the mariadb-Container
could  not be started.

I just did a docker start mariadb which faulted with:
FATA[0002] Error response from daemon: Cannot start container 93ae91947b95944769c43a7665e4158d7f2becf4a137427cff8fd17a61485bf6: write /sys/fs/cgroup/memory/system.slice/docker-93ae91947b95944769c43a7665e4158d7f2becf4a137427cff8fd17a61485bf6.scope/memory.memsw.limit_in_bytes: invalid argument

Because my container was already runnig since some time, I rebuilt the
container and started again, but the message appeared again. My start command was:


docker run --name="mariadb" --hostname="mariadb" --dns=X.X.X.X --dns-search=example.com -c 100 -m 1g -d -P -v /home/ewer/prod/docker/maria_db:/data/mysql ewer/mariadb

After removing the "-m 1g" option, the container could be started again.

There must have been some change during one of the last updates,
because the container could be started on Fedora 21 with the memory limit.


Jan 20, 2015

copy buffer from tmux/tmuxinator ( terminal multiplexer ) to the X-Clipboard

tmux ( tmuxinator for configuration and start of a configured session )
allows to open in one terminal multiple shells and split the window and so
on.

To copy data from the shell you must scroll up most of the time.

Scrolling is done by

<bind-key> - <screen up>.

In My case <Ctrl-A><screen up>

If you want to select enter selection mode with <bind-key><[>

Pressing <SPACE> sets the start mark and <RETURN> finishes the selection.

To get the buffer from tmux into the X-clipboard I found the following hint
here:

# Copy into clipboard
bind C-c choose-buffer "run \"tmux save-buffer -b '%%' - | xclip -i -selection clipboard\""
# Paste from clipboard
bind C-v run "xsel -o -b | tmux load-buffer - && tmux paste-buffer"
# Copy into primary
bind C-y choose-buffer "run \"tmux save-buffer -b '%%' - | xsel -i\""
# Paste from primary
bind C-p run "xsel -o | tmux load-buffer - && tmux paste-buffer"
 

After adding this commands you can copy the selected buffer with
<bind-key><C-c> and the X-clipboard has the data.


Update: 
 
 After doing a C-c to copy the chosen buffer to the clipboard, the bind key of tmux 
 doesn't work anymore. After reading through a bug-message here, I had to change the 
 binding a little bit by adding -b to the run command: 
bind C-c choose-buffer "run -b \"tmux save-buffer -b '%%' - | xclip -i -selection clipboard\""

otherwise xclip is running forever blocking further tmux commands. 

Jan 16, 2015

Upgrade from JBoss 7.0 to 7.2 and mariadb as database with mysql-JDBC driver caused exception during JPA Update

Now I had to upgrade the JBoss from 7.0 to 7.2 everything else was the same.
A Timer-EJB attempted to update data by JPA  in the database
which is a docker instance with MariaDB. This update caused Exceptions.

Now I've installed a new module with the JDBC-Driver from MariaDB.

After installating the module, adding a driver and changing the driver from
mysql to mariadb ( keeping the JDBC-URL on jdbc:mysql:.... ) , the
exceptions disappeared.

Jan 8, 2015

activate gedit plugins in Fedora 21 with Gnome 3.14

Fedora 21 has many plugins for GEdit, which must be installed as packages.

$ sudo dnf search gedit
===================================================================== N/S Matched: gedit =====================================================================
gedit.x86_64 : Text editor for the GNOME desktop
gedit-plugins.x86_64 : Plugins for gedit
gedit-plugin-git.x86_64 : gedit git plugin
gedit-plugin-charmap.x86_64 : gedit charmap plugin
gedit-plugin-synctex.x86_64 : gedit synctex plugin
gedit-plugin-terminal.x86_64 : gedit terminal plugin
gedit-plugin-textsize.x86_64 : gedit textsize plugin
gedit-plugin-bookmarks.x86_64 : gedit bookmarks plugin
gedit-plugin-commander.x86_64 : gedit commander plugin
gedit-plugin-dashboard.x86_64 : gedit dashboard plugin
gedit-plugin-joinlines.x86_64 : gedit joinlines plugin
gedit-plugin-multiedit.x86_64 : gedit multiedit plugin
gedit-plugin-zeitgeist.x86_64 : gedit zeitgeist plugin
rabbitvcs-gedit.x86_64 : Gedit extension for RabbitVCS
gedit-plugin-drawspaces.x86_64 : gedit drawspaces plugin
gedit-plugin-codecomment.x86_64 : gedit codecomment plugin
gedit-plugin-colorpicker.x86_64 : gedit colorpicker plugin
gedit-plugin-smartspaces.x86_64 : gedit smartspaces plugin
gedit-plugin-colorschemer.x86_64 : gedit colorschemer plugin
gedit-cossa.x86_64 : gedit plugin for GTK+ themes previewing
gedit-plugin-wordcompletion.x86_64 : gedit wordcompletion plugin
gedit-plugin-bracketcompletion.x86_64 : gedit bracketcompletion plugin
gedit-latex.x86_64 : gedit plugin for composing and compiling LaTeX documents
gedit-devel.x86_64 : Support for developing plugins for the gedit text editor
gedit-devel.i686 : Support for developing plugins for the gedit text editor
gedit-beesu-plugin.x86_64 : Allows normal users to open files in gedit as root
gedit-code-assistance-devel.i686 : Development files for gedit-code-assistance
gedit-code-assistance-devel.x86_64 : Development files for gedit-code-assistance
gedit-code-assistance.x86_64 : gedit plugin for code assistance for C, C++ and Objective-C
gedit-code-assistance.i686 : gedit plugin for code assistance for C, C++ and Objective-C
gedit-plugins-data.x86_64 : Common data required by plugins

After starting of GEdit in Gnome 3.14, I didn't find any menu-item to activate the plugins.

The "tricky" part is to get the preference menu from the top bar of the
gnome desktop as seen in the picture below:



Here you get the preferences window, in which you can activate the plugins.