Using xdpyinfo to display information utility for X

According to the manual page, xdpyinfo is a useful utility for diaplaying information about an X server. It can be used to examine

1. Capabilities of the server
2. Predefined values for various parameters in communicating between clients and the server
3. Different types of screen and visuals available

Commands to use

# xdpyinfo -display :0

Using TurboVNC 0.6 and VirtualGL 2.1.4 to run OpenGL Application Remotely on CentOS

For more information on Using TurboVNC 0.6 and VirtualGL 2.1.4 to run OpenGL Application Remotely on CentOS on Linux Cluster

“VirtualGL is an open source package which gives any Unix or Linux remote display software the ability to run OpenGL applications with full 3D hardware acceleration…..With VirtualGL, the OpenGL commands and 3D data are instead redirected to a 3D graphics accelerator on the application server, and only the rendered 3D images are sent to the client machine……” For more information see What is VirtualGL? from Project Website"

Using glxgears to report Frame Per Second

glxgears is an OpenGL program that reports FPS (frames per second) numbers. I find this program useful to test out OpeGL Renderer such as simple comparison between VNC, VirtualGL and of course the Direct-From-The-Machine itself.

For TurboVNC (unencrypted) churned out about on a Local LAN

# glxgears
6028 frames in 5.1 seconds = 1186.369 FPS
6000 frames in 5.1 seconds = 1178.267 FPS
5760 frames in 5.1 seconds = 1132.999 FPS
5760 frames in 5.1 seconds = 1133.431 FPS
5520 frames in 5.0 seconds = 1096.104 FPS
5147 frames in 5.0 seconds = 1027.200 FPS
5160 frames in 5.1 seconds = 1016.540 FPS
5160 frames in 5.1 seconds = 1016.316 FPS
5160 frames in 5.1 seconds = 1016.578 FPS
5160 frames in 5.1 seconds = 1016.974 FPS
5160 frames in 5.1 seconds = 1018.695 FPS

For SSH and Xming churned out about on a Local LAN. But the glxgears image refresh is definitely slower than TurboVNC even though the FPS is similar.

# glxgears
6761 frames in 5.0 seconds = 1345.283 FPS
7022 frames in 5.2 seconds = 1343.998 FPS
7021 frames in 5.2 seconds = 1337.664 FPS
6632 frames in 5.1 seconds = 1288.340 FPS
6632 frames in 5.1 seconds = 1297.666 FPS
6760 frames in 5.2 seconds = 1309.137 FPS
6632 frames in 5.2 seconds = 1266.929 FPS
7022 frames in 5.3 seconds = 1330.755 FPS
6631 frames in 5.1 seconds = 1309.255 FPS
6632 frames in 5.0 seconds = 1314.089 FPS
6891 frames in 5.3 seconds = 1305.207 FPS
6631 frames in 5.1 seconds = 1291.670 FPS

For Direct-From-The-Machine. This is the best performance

# glxgears
61237 frames in 5.0 seconds = 12247.371 FPS
65314 frames in 5.0 seconds = 13062.798 FPS
60291 frames in 5.0 seconds = 12058.135 FPS
64627 frames in 5.0 seconds = 12925.391 FPS
64976 frames in 5.0 seconds = 12995.109 FPS
64949 frames in 5.0 seconds = 12989.766 FPS
64961 frames in 5.0 seconds = 12992.117 FPS
64953 frames in 5.0 seconds = 12990.459 FPS
64920 frames in 5.0 seconds = 12983.886 FPS

For VirtualGL on VGL Image Transport with a Direct X11 Connection. Performance is very good near Direct-From-The-Machine

6559 frames in 5.0 seconds = 1311.784 FPS
6573 frames in 5.0 seconds = 1314.600 FPS
6548 frames in 5.0 seconds = 1309.470 FPS
6547 frames in 5.0 seconds = 1309.399 FPS
6545 frames in 5.0 seconds = 1308.945 FPS
6544 frames in 5.0 seconds = 1308.787 FPS
6527 frames in 5.0 seconds = 1305.391 FPS
6527 frames in 5.0 seconds = 1305.336 FPS

Hadoop Communites in Facebook

Hadoop Communites in Facebook

1. Hadoop Group in Facebook
2. Singapore Hadoop Group in Facebook

Welcome.conf and Apache Default web Page

In CentOS and Fedora, the default Document Root is /var/www/html. If the user does not have a index.htm page in their directory, Apache will show a web page "Apache 2 Test Page" Power by CentOS

I think you may ask where is the web page coming from since there is no starting web page. To locate this "
"starting page", go to

# less /etc/httpd/conf.d/welcome.conf

The easier way to "remove" the Default Web Page is by creating a starting web page or a redirect web page