Installing gcc4 on CentOS 4 from the command line

This is a very simple entry today. I wanted to install gcc 4.x on CentOS 4. But whenever you do a yum install gcc, it gets gcc 3.4.6. Of course, I try yum install gcc4 and was not able to get the package either. I manage to get it only when I

yum install gcc*

Encountering LimitRequestBody and memory_limit for Gallery

When you are uploading file, you may encounter this error:
"You may need to set LimitRequestBody 16777216 and memory_limit = 64M in /etc/php.ini and /etc/httpd/conf.d/php.conf on your Gallery server"

To solve the issue, change the /etc/php.ini file to

vim /etc/php.ini
upload_max_filesize = 128M 

Edit the following as well for /etc/httpd/conf.d/php.conf

vim /etc/httpd/conf.d/php.conf
<Files *.php>
SetOutputFilter PHP
SetInputFilter PHP
LimitRequestBody 33554432
</Files>

Force Rebooting Remotely without corrupting the file system

Must thanks to Gavin W. Burris for his interesing blog Remotely Force a Reboot which hightlighted Magic SysRq as a cool tool to force a reboot remotely.

Step 1: To enable SysRq key

# echo 1 > /proc/sys/kernel/sysrq

Step 2: Power cycle the machine

echo b > /proc/sysrq-trigger

For more information, read Wikipedia Magic SysRq

Testing for Saturated Network for NFS

How do we test for saturated network for NFS. Is there a systematic way of doing it? You can read my Linux Cluster blog entry Testing for Saturated Network for NFS

Multi-core Strategies: MPI and OpenMP

Multi-core Strategies: MPI and OpenMP is an interesting article on MPI and OpenMP from HPCommunity.org