With MPI-IO we see various alternatives for programming file I/O. The overall program performance depends on many different factors. A new trace analysis environment provides deeper insight into the client/server behavior and visualizes events of both process types. We investigate the influence of making independent vs. collective calls together with access to contiguous and non-contiguous data regions in our MPI-IO program. Combined client and server traces exhibit reasons for observed I/O performance.

@inproceedings{AOTMOLWTPJ07,
	author	 = {Thomas Ludwig and Stephan Krempel and Michael Kuhn and Julian Kunkel and Christian Lohse},
	title	 = {{Analysis of the MPI-IO Optimization Levels with the PIOViz Jumpshot Enhancement}},
	year	 = {2007},
	booktitle	 = {{Recent Advances in Parallel Virtual Machine and Message Passing Interface}},
	editor	 = {Franck Cappello and Thomas Hérault and Jack Dongarra},
	publisher	 = {Springer},
	address	 = {Berlin / Heidelberg, Germany},
	series	 = {Lecture Notes in Computer Science},
	number	 = {4757},
	pages	 = {213--222},
	conference	 = {EuroPVM/MPI-07},
	organization	 = {Institut national de recherche en informatique et automatique},
	location	 = {Paris, France},
	isbn	 = {978-3-540-75415-2},
	doi	 = {http://dx.doi.org/10.1007/978-3-540-75416-9_32},
	abstract	 = {With MPI-IO we see various alternatives for programming file I/O. The overall program performance depends on many different factors. A new trace analysis environment provides deeper insight into the client/server behavior and visualizes events of both process types. We investigate the influence of making independent vs. collective calls together with access to contiguous and non-contiguous data regions in our MPI-IO program. Combined client and server traces exhibit reasons for observed I/O performance.},
	url	 = {http://www.springerlink.com/content/p475547454373863/fulltext.pdf},
}