@InProceedings{chen:panda-model, author = {Y. Chen and M. Winslett and S. Kuo and Y. Cho and M. Subramaniam and K. E. Seamons}, title = {Performance Modeling for the {Panda} Array {I/O} Library}, booktitle = {Proceedings of Supercomputing '96}, year = {1996}, month = {November}, publisher = {ACM Press and IEEE Computer Society Press}, URL = {http://www.supercomp.org/sc96/proceedings/SC96PROC/YING/INDEX.HTM}, keywords = {performance modeling, parallel I/O, pario-bib}, abstract = {We present an analytical performance model for Panda, a library for synchronized i/o of large multidimensional arrays on parallel and sequential platforms, and show how the Panda developers use this model to evaluate Panda's parallel i/o performance and guide future Panda development. The model validation shows that system developers can simplify performance analysis, identify potential performance bottlenecks, and study the design trade-offs for Panda on massively parallel platforms more easily than by conducting empirical experiments. More importantly, we show that the outputs of the performance model can be used to help make optimal plans for handling application i/o requests, the first step toward our long-term goal of automatically optimizing i/o request handling in Panda.}, comment = {On Web and CDROM only. They derive a detailed but fairly simple model of the Panda 2.0.5 parallel I/O library, by carefully enumerating the costs involved in a collective I/O operation. They measure Panda, AIX, and MPI to obtain parameters, and then they validate the model by comparison with the actual Panda implementation running a basic benchmark and an actual application. The model predicts the benchmark performance very well, and is as much as 20\% off on the performance of the application. They have embedded the performance model in a "simulator", which predicts the performance of a given sequence of collective I/O requests, and they plan to use it in future versions of Panda to formulate I/O plans by predicting the performance resulting from several different Panda parameter settings, and choosing the best.} }