Study Notes

A Linux command line: find -name ‘file_name’. its purpose is to find out specific file usring file_name string. I think this command does not do better than “locate” which is more convenient for type.

HPC Benchmarking. The sales are always asked for Benchmarking of the product by the customers in whose mind Benchmarking indicates the performance would help them to select from so many products. In the Lab, we will tuning the system’s structure, for example, If we have four processors(CPU), there are three strategy of distribution. One schema is 4 processors are all on one node, if each node has one processor is also included in the strategy, and perhaps for the best performance, we put two cpus in two machines so that each node has two processors. finally we can determine which hardware to purchase.

What can be done to improve the Benchmark?
—— Modify the data.
—— Tune the application, such as better complier, better libraries, and modify the benchmark code itself.(There are many libraries in the market now, netlib.org and GOTO are opensource, but MPC from Intel must be purchased for business license.However, the former two lib do not supply unbreakable support as Intel’s MPC)
—— Change the hardware.(As we all know, the best rate of EtherNet will be 50-60%,and the InfiniBand will get about 70%). If more money is costed on nodes, less money is costed on communicating hardware, for example, switch, copper line of EtherNet. On the contract, more money is costed on hardware, less money is costed on nodes).

In the Intel trainning camp. HPLinpack is used to indicate Benchmark. Before HPLinpack test start, the Hyper-threading must be off because Hyper-threading technology confused the HPLinpack software.

To tuning performance, the litter value could be ignored or not is usually important to improve performance. we should test and test to find the right answer.

Cluster management tools packages include Portable Batch System(PBS),LSF and SGE. PBS and SGE is open-souce. LSF comes from Canada. In the traing lessons, we put attention on SGE, Sun Grid Engine. which originally developed by Gridware, a company departed from SUN.
We could see the masters and nodes’ statues in the Web brower(Moziila). There is not direct iron in ROCK linux, we run the moziila through click “run applications” and input the localhost IP address. Then three nodes’ details are all displayed in the Web Page writen by PHP.
In the items listed in the former web page, Ganglia is contained because it is installed by ROCKs automatically. Ganglia is used to monitor the cluster in GUI environment.