Sunday, December 23, 2007

Recover the Linux Boot Loader (Grub)

Most of the Linux users who are using multiple operating systems installations in a single hard drive. Many of them (Especially those of Microsoft's) have to encounter the erasure and re-writing of MBR (Master Boot Record) after re-installing or fresh installing Windows after Linux. This situation is very frustating as despite the Linux partition being intact, one has to reinstall the Linux distribution everytime after installation of Windows.
By issuing the below commands, one can retrieve his/her previous Grub Bootloader screen in 6 easy steps.
  • You need a bootable Linux CD (Preferably a live CD)
  • Please note that the Linux partiton for which you are going to recover the MBR should be installed on an un-encrypted filesystem
  • Boot with the bootable linux CD
  • Invoke the shell
  • Give the following commands
  • # grub (This will drop you on the grub prompt)
  • grub>geomettry (hd0) (Your Primary Hard Drive. Determine the Linux Partition number say "n")
  • grub>root (hd0,n) ("n" is your linux partition searched by the previous command)
  • grub>setup (hd0,n)/boot/grub/menu.lst
  • quit

Voila!!.... just restart your computer and find your previous MBR restored!!

Sunday, December 16, 2007

All new Top500 along with one at India in Top5

The latest Top500 list was rejuvinated with a never before 478.2 TFop/s delivered by as ususal much discussed the BlueGene/L System, (a joint development of IBM and the Department of Energy's (DOE) National Nuclear Security Administration (NNSA) and installed at DOE's Lawrence Livermore National Laboratory in Livermore, the United States) breaking its own record of 280.6 TFop/s. There were many new players seen sucha as for the first time ever, India placed a system in the Top 10. The Computational Research Laboratories, a wholly owned subsidiary of Tata Sons Ltd. in Pune, India, installed a Hewlett-Packard Cluster Platform 3000 BL460c system. achieved 117.9 TFlop/s performance.
The Top5 list as follows:
United States

3 SGI/New Mexico Computing SGI Altix ICE 8200, Xeon quad SGI
Applications Center (NMCAC)
United States
For more results please visit:

Friday, June 29, 2007

2007's first Top500 list is out leaded by BlueGene!

As I disclosed in my one later post dated Sunday, May 20, 2007 I am posting a yet another post on fastest supercomputer of the world. The list was published during at the International Supercomputing Conference (ISC ’07) in Dresden, Germany ( on June 27, 2007. Who else it can be other than BlueGene??

Yes, IBM BlueGene ( installed at Lawrance Livermore National Laboratories, US ( topped on the list for the consequent forth time since its commissioning by delivering a stunning and steady 280.6 Teraflops! (Trillions of computations per second). In addition there were two other Supers which crossed the 100 Tflop mark -- the upgraded Cray XT4/XT3 at Oak Ridge National Laboratory, ranked No. 2 with a benchmark performance of 101.7 TFlops and Sandia National Laboratory’s Cray Red Storm system, which ranked third at 101.4 TFlops.

Sunday, June 17, 2007

The unending π game

This unending figure has always attracted philosphers, mathematicians, scientists, engineers and programmers ever since last 4 Millenia. A few intersting links of the efforts made by them are listed as below. Any addenda to the same are always welcome.
  1. A very good history of these efforts :
  2. An illustrative collection of different methods for calculating this magic figure:
  3. Algortihms and code to achieve π (PI) for mathamatics and computer science experts:
  4. An incradible PI search page to find digits upto 200 million PI digits:
  5. Collection of PI formula applied by various people:
  6. A nice collection of binaries as well as sources programs for PI:

Friday, June 1, 2007

Fedora 7 is released excluding the "Core"!!

After almost 24 months of continuous development and 6 concurrent core releases, Red Hat supported the Fedora was finally released as Fedora 7 alone excluding the core factor and combining the core and extras on May 31, 2007 (Just Yesterday!). It is considered to be the most stable version amongst its previous variants packed with varios features including various Spins, increased start-up and shut-down speed, secured wireless, support for encrypted FS, beautiful themes and many more to be found at
In total F7 must be provided a few GB of space in your hard drive! (Now even live CD and a small bootable iso image is also available). So grab it now from here:

Sunday, May 20, 2007

From Giga Flop to Tera Flop!

The performance delivered by any Super Computer has increased anything, like a rocket ever since their inception! Continuous implementations in microprocessor and semiconductor technology, interconnections and relatively the never failing Moore's law have always hiked the pick performance of a Supercomputer year by year.
Within just about a decade, now some of the top Supercomputers deliver their performance in Teraflops and hence, talking and measuring them in Gigaflops has become like a history. ( is an official benchmarking group that measures the top notch delivery of 500 most powerful Supercomputers by using the high performance linpack ( benchmark as a yardstick twice a year.
Let us now examine the peak performance of some the top500 #1 ranking Supercomputers in the last decade. :
This was the first phase:
  • Intel Paragon XP/S @ Touchstone Delta System CalTech, 1993, 143.4 Gigaflops
  • Fujitsu Numerical Wind tunnel @ National Aerospace Laboratory Japan, 1993, 170 Gigaflops
  • Thinking Machine Corporation, CM-5, 1995
  • Hitachi CP-PACS, 368.2 Gigaflops, 1996

Here comes the second phase: (Observe the hike in performance)

  • IBM ASCI-Red @ Sandia National Laboratories, New Mexico, 1338 Gigaflops, 1997
  • IBM ASCI-Red @ Sandia National Laboratories, New Mexico, 2121 Gigaflops, 1999
  • IBM ASCI-White @ LLNL, 7304 Gigaflops, 2000

Here comes the third but slightly short phase:

  • NEC, The Earth Simulator @ the Earth Simulator Center (ESC), Japan, 35860 Gigaflops, 2002

Finally Supercomputers delivers @ Teraflops, it is really increadible.

  • IBM Blue Gene @ LLNL, 280.6 Teraflops (An increadible 280600 Gigaflops), on the top since 2004

Friends, this progress is just a glimpse of last 13-15 years, but the entire hardware as well as software technology behind this phenomena is now around almost 65 years old. To conclude this entery we have to remember Mr. Gordon Moore once again to just predict the future of Supercomputing!!

By the way the next list of top500 is to be launched in the June 2007 at ISC 07, Germeny ( We will be back here again on this topic as the new list is declared..... till then wait for YABP!

Monday, May 14, 2007

Emulators Watch - 2007

Hey friends, we are going to discuss emulators useful for geeks and not for gamers (though many times a geek is found a gamer and vice versa!). Some of the links of popular emulators as follow.

Tuesday, May 8, 2007

Free Operating Systems/Linux @ Education

This post in our blog may seem to be slight different from the previous ones. As it concerns with more to social issue rather than the technical ones. Although the Free and Open Source Software has always direct concerns with the society, more specifically liberalised and free society.

Well, there has been many educational Linux distributions which are specially engineered for the school going children. This distros are packed with educational games as well as easy to use scientific, mathematical and astronomical software which prove very much useful in their education. Some the links are as follow:

So this list is not ending here, there is lot contributed for education.

Saturday, April 28, 2007

How SSI Cluster differ from PVM Cluster?

SSI stands for Single System Image which is the simplest way of High Performance Computing, it uses a clustering middleware such as openMosix ( In the SSI cluster, all the member nodes in a Local Area Network collectively deliver performance as single virtual machine.


  • Very easy to setup.
  • No special hardware and software requirements.
  • Applications need not to be recompiled for multicomputing environment.


Batch processing aaplications such as Backup(tar+zip) for mulitple files, Media Format Conversion for mulitiple files, Content filtering and e-mail virus scanning etc.


PVM stands for Parallel Virtual Machine, in which the cluster distributes a single task into crunches and processes them individually over the member nodes of the cluster. However, a major issue with this type of custering is the recompilation of the application with the PVM/MPI (Parallel Virtual Machine/Massge Passing Interface) libraries such as OpenMPI ( or OSCAR (


  • Can distribute a single task requireing higher CPU Throughput into multiple sub-tasks.
  • Node job assignment and thread management is taken care by parallely compiled application itself.


Applications that require more CPU crunching such as scientific applications, data modelling, weather forecasting etc.

Sunday, April 22, 2007

Three Extreme Distors in a Month!

The April month of this year proved to be the a milestone in releases of various popular GNU/Linux distros. It started with the release of longly awaited Debian 4.0 (aka Debian etch) on April 8, 2007. Then there was the turn of CentOS 5.0 and finally Ubuntu 7.04 (aka Feisty Fawn) was released on April 19, 2007.

Friday, April 13, 2007

Benchmarking Cluster Performance with Linpack 1.0a

Everyone knows that Linpack ( is the de-facto standard for benchmarking a multiecomputer's performance under load conditions caused by complex mathematical computations. Even the official high performance measuring project Top500 ( also uses Linpack itself as a yardstick of high performance computing measurement.
I also tested and benchmarked the performance of a small cluster through the High Performance Linpack benchmark 1.0a ( and and found the following results.
In addition I must comment that it took no time to set up a cluster by using the ParallelKnoppix distro ( as the distro itself being a live-cd based on auto node discovery.
So, let's talk lesser and see how were the results??!!
Benchmarking Date: April 13, 2007
Platform: ParallelKnoppix version 2.4 (23-Feb-2007)
No. of nodes:3 + 1 Master machine
CPU: 1 x Pentium 4 HT @ 2.4 GHz on each node as well as server
RAM: 256 MB on each node as well as server
Inerconnect: Gigabit Realtek NIC connected through 24 port 100 mbps, HCL fast ethernet managed swtich
And the benchmarked result was 2.35867 Giga-Flops!

Thursday, March 29, 2007

How to Setup a Cluster with Live CD?

Since the Live CDs have become ever popular, playing with an alternative OS has become very much simple yet effective. Even High Performance Computing is not untouched from the Live CD revolution. Initially, a Cluster or a High Performance Computing environment was only a cup of tea for those organizations with six figure annual budgets. But now anyone having LANed computers (Preferably with Gigabit) can easily turn his/her network in to a true High Performing Cluster by using just a Live CD with an OS preconfigured with a parallel computing middleware such as OpenMOSIX, OSCAR etc.

You can download any of the following live CDs for HPC environment:

ClusterKnoppix from :
The Bootable Cluster CD from :
Boot each node in a network by popping up the live CD and configure the network addresses and eventually convert your office network to a High Performance Cluster ready in no time!

Tuesday, March 13, 2007

How should I migrate to Open Source/ Free Software/ Linux ?

Many times it has been observed that people just refuse to be migrated towards the Free/Open Source software on account of their "so called" less user friendlienss and non portability. Further, it is repeatedly stated that the free software does not fulfill a person's exact requirement.
However, in real sense, this is quite opposite as Newton's III'd law!! Migrating to the Free Software was and is the easier task ever. And a wide range of free software is always available right from a kid user to an end user to a power user to a developer to a gamer to a CXO of an enterprise and last but not the least a Hacker!
A few steps stated below are enough for anyone wishing to get rid of the trap of proprietary software and open the doors towards the universe of the Free Software:

  • Go for the GNUWin II CD project for a large list of free software ported to the Windows platform (
  • Download and Install cygwin from which provides almost linux like command interpreter and other related environment which will accordingly make familier with the Linux look and feel.
  • Bring a live Linux CD such as Knoppix from your friend or download the same from, by using this you will be able to taste the real Linux without even touching your hard-drive.
  • Now you should be enough satisfied with the advantages of the Free and Open Source software so you may migrate to any distribution of Linux available and be collectively found at, although I personally advice Ubuntu based on Debian from as a good starter.
  • And do not forget to count yourself a Linux user at !!

Saturday, March 3, 2007

Some known Operating System resources!

The followings are some good Operating System resources:

A dedicated OS search engine:

The Operating System Resources Centre:

BonaFide OS development news and tutorials:

Linux from Scratch and beyond:

The Linux Documentation Project:

Wednesday, February 21, 2007

X11R7.2 Released community released the latest version of X window system supporting right from Linux, BSD, Solaris, GNU Hurd and Microsoft Windows on last February 15, 2007 with a view of stability and bugfixes.
By the release of this third modular version, X window system i.e. X11R7.2 is now equipped with several improved features such as autoconfiguration heuristiecs, increased support for the openGL based desktop managers such as Beryl ( and Compiz ( with enhanced XACE security policy framework.

This opensource graphical server can be downloaded freely from

Monday, February 19, 2007

Plan 9, Back to the Seventies!

Back to Seventies?! well, as the title suggests, Plan 9's evolution should be considered to be back in the era of early seventies when geeky research and development associates were engaged in implementing The UNIX and C at the Bell Labs. Yes, Plan 9 has initially been developed by Ken Thompson, Rob Pike, Dave Presotto, and Phil Winterbottom at the Bell Labs in 1980s, and later on by the many other associates.

Plan 9, is currently in 4th release since 1992 must not be considered as a yet another UNIX or Linux clone. It's a completely different operating system written right from the scratch for the purpose of research and development.

However, it should not be considered to be limited to academic and research purposes only. Vita Nuova present exclusively distributes and provides training and support for the Plan 9.

To directly boot from the hard disk, Plan 9 should be installed on a primary partition, otherwise for a floppy boot it can be accommodated in a secondary one.

So, Plan 9 is must for every OS lover who really wants something else than the routines!!

Saturday, February 17, 2007

Introduction to MINIX 3

MINIX 3 is the youngest member i.e. a latest release of MINIX -- the operating system family written right from scratch initially by Prof.Andrew Tannenbaum (ast) and now maintained by the associates of Vrije University ( at the Netherlands.

Initial versions i.e. MINIX 1 and 2 were more specific for academic purposes. But this latest release can seriously be considered as an alternative operating system for adoption where there are scarce financial as well as system resources.

The most important feature that makes this operating system to be more effective for older/slower/embeded machines over other operating systems is the Microkernel, that consist of only about 4000 lines of code in contrast to the other operating systems' kernels (Windows, Linux and Solaris) being packed with tonnes of lines of code. Furthermore, the device drivers in this operating system runs as an independent user level modules hence, whenever any device dirver fails to respond the reincarnation server restarts the process automatically which prevents the computer from hanging. Other advantages offering the high reliability to the MINIX 3 are such as but not limited to: prohibited device drivers' memory access, buffer overrun protection, protected I/O port access to drivers etc. It can even be installed on a 386/486/Pentium and above machines with as low as 16 MB of RAM and 70-80 MB of free diskspace. Hence, it also projected the operating system for MIT's 100$ laptop - one laptop per child project (

Being small in size and compatible for a smaller/older hardware doesn't mean that the system is not feature rich! The POSIX standard compliant operating system comes with about 400 programs with which all the UNIX/Linux geeks are familier.

Last but not the least the OS is open source, freely distributed under BSD style license and community developed, hence it is a smarter choice for anyone who wants something else than Windows "and" Linux.
This OS can be downloaded from

-- Xitij Shukla
SRK College of Management and Computer Education, Bhuj, INDIA
Special thanks to

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