COMSOL: How to enable the eclipse internal browser on Ubuntu 12.04

by installing libwebkitgtk in Ubuntu

sudo apt-get install libwebkitgtk-1.0-0

How do I update a CentOS server's time from an authoritative time server?

yum install ntp
chkconfig ntpd on
ntpdate pool.ntp.org
service ntpd start

Mount SWAP on Amazon EC2

By default the amazon instance is going without swap. So you need to create and attach a volume mkswap /dev/xvdn Then use the commnad swapon /dev/hdxx where /dev/hdxx is your new swap partition (or swap file). You can use more than one swap partition/file just by enabling swap on all the swap files/partitions your system knows about with swapon -a.

How to mount a VirtualBox VDI image

sudo apt-get install qemu-utils
modprobe nbd
qemu-nbd -c /dev/nbd0 <vdi-file>
mount /dev/nbd0p1 /mnt


umount /mnt
qemu-nbd -d /dev/nbd0

ExaFMM installation

ExaFMM is written in C++/CUDA OpenMP/MPI. Code is available from: https://bitbucket.org/exafmm/exafmm. A development version with higher performance but less features is available from: https://bitbucket.org/rioyokota/exafmm-dev.

The code requires CUDA. If you used Ubuntu 12.04, the steps are as follows.

1. Install the Nvidia driver.

2. Install requisite tools

sudo apt-get install freeglut3-dev build-essential libx11-dev libxmu-dev libxi-dev libgl1-mesa-glx libglu1-mesa libglu1-mesa-dev

3. Download the CUDA tools. 

4. Add requisite lines  to the end of ~/.bashrc (the nice example is here ) as follows

 export PATH=$PATH:/usr/local/cuda-5.0/bin
 export LD_LIBRARY_PATH=/usr/local/cuda-5.0/lib64:/lib
5. If a problem arises with libglut, find it with

    sudo find /usr -name libglut\*

    Now we can create a softlink to it

   sudo ln -s /usr/lib/x86_64-linux-gnu/libglut.so.3 /usr/lib /libglut.so