author	 = {Tien Duc Tien},
	title	 = {{Tracing Internal Behavior in PVFS}},
	advisors	 = {Thomas Ludwig and Julian Kunkel},
	year	 = {2009},
	month	 = {10},
	school	 = {Ruprecht-Karls-Universität Heidelberg},
	howpublished	 = {{Online \url{}}},
	type	 = {Bachelor's Thesis},
	abstract	 = {Nowadays scientific computations are often performed on large cluster systems because of the high performance they deliver. In such systems there are many reasons for bottlenecks which are related to both hardware and software. This thesis defines and implements metrics and information used for tracing events in MPI applications in conjunction with the parallel file system PVFS in order to localize bottlenecks and determine system behavior. They are useful for the optimizations of the system or applications. After tracing, data is stored in trace files and can be analyzed via the visualization tool Sunshot.

		  There are two experiments made in this thesis. The first experiment is made on a balanced system. In this case Sunshot shows a balanced visualization between nodes, i.e. the load between nodes looks similar. Moreover, in connection with this experiment the new metrics and tracing information or characteristics are discussed in detail in Sunshot. In contrast, the second experiment is made on an unbalanced system. In this case Sunshot shows where bottlenecks occurred and components which are related.},