Parallelization of a hydrological model using the message passing interface
نویسندگان
چکیده
With the increasing knowledge about the natural processes, hydrological models such as the Soil and Water Assessment Tool (SWAT) are becoming larger and more complex with increasing computation time. Additionally, other procedures such as model calibration, which may require thousands of model iterations, can increase running time and thus further reduce rapid modeling and analysis. Using the widely-applied SWAT as an example, this study demonstrates how to parallelize a serial hydrological model in a Windows environment using a parallel programing technologydMessage Passing Interface (MPI). With a case study, we derived the optimal values for the two parameters (the number of processes and the corresponding percentage of work to be distributed to the master process) of the parallel SWAT (P-SWAT) on an ordinary personal computer and a work station. Our study indicates that model execution time can be reduced by 42%e70% (or a speedup of 1.74e3.36) using multiple processes (two to five) with a proper task-distribution scheme (between the master and slave processes). Although the computation time cost becomes lower with an increasing number of processes (from two to five), this enhancement becomes less due to the accompanied increase in demand for message passing procedures between the master and all slave processes. Our case study demonstrates that the P-SWAT with a fiveprocess run may reach the maximum speedup, and the performance can be quite stable (fairly independent of a project size). Overall, the P-SWAT can help reduce the computation time substantially for an individual model run, manual and automatic calibration procedures, and optimization of best management practices. In particular, the parallelization method we used and the scheme for deriving the optimal parameters in this study can be valuable and easily applied to other hydrological or environmental models. Published by Elsevier Ltd. Software availability Name of software: P-SWAT Description: The watershed model SWAT is parallelized using a parallel programing technology (MPI) to enhance the execution efficiency on the Microsoft Windows platform. Developers: Y. Wu and T. Li Source language: Fortran Software availability: Contact the developers logy Solutions, U.S. Geological ce (EROS) Center, Sioux Falls, tsinghua.edu.cn (T. Li). r Ltd.
منابع مشابه
MPI- and CUDA- implementations of modal finite difference method for P-SV wave propagation modeling
Among different discretization approaches, Finite Difference Method (FDM) is widely used for acoustic and elastic full-wave form modeling. An inevitable deficit of the technique, however, is its sever requirement to computational resources. A promising solution is parallelization, where the problem is broken into several segments, and the calculations are distributed over different processors. ...
متن کاملLearning from the Success of MPI
The Message Passing Interface MPI has been extremely successful as a portable way to program high performance parallel com puters This success has occurred in spite of the view of many that mes sage passing is di cult and that other approaches including automatic parallelization and directive based parallelism are easier to use This paper argues that MPI has succeeded because it addresses all o...
متن کاملDynamic parallelization of hydrological model simulations
1 This paper introduces the development of a dynamic parallel algorithm for conducting 2 hydrological model simulations. This new algorithm consists of a river network 3 decomposition method and an enhanced master-slave paradigm. The decomposition 4 method is used to divide a basin river network into a large number of subbasins, and the 5 enhanced master-slave paradigm is adopted to realize the...
متن کاملTo Parallelize or Not to Parallelize, Speed Up Issue
Running parallel applications requires special and expensive processing resources to obtain the required results within a reasonable time. Before parallelizing serial applications, some analysis is recommended to be carried out to decide whether it will benefit from parallelization or not. In this paper we discuss the issue of speed up gained from parallelization using Message Passing Interface...
متن کاملJournal of Environmental Hydrology
Journal of Environmental Hydrology Volume 17 Paper 7 February 2009 1 A parallelized large-scale regional hydrologic soil model (RHSM) is developed as a tool for large-scale unsaturated zone investigations. It is applied to simulate the temporal and spatial responses of the unsaturated zone and the regional water budget under the forcing of realistic precipitation and evaporation scenarios. The ...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- Environmental Modelling and Software
دوره 43 شماره
صفحات -
تاریخ انتشار 2013