masterParallel.m

function [fOutVar,nBlockPerCPU, totCPU] = masterParallel(Parallel,fBlock,nBlock,NamFileInput,fname,fInputVar,fGlobalVar,Parallel_info,initialize)
% PARALLEL CONTEXT
% This is the most important function for the management of DYNARE parallel
% computing.
% It is the top-level function called on the master computer when parallelizing a task.
%
% This function has two main computational strategies for managing the
% matlab worker (slave process):
%
% 0 Simple Close/Open Stategy:
%   In this case the new Matlab instances (slave process) are open when
%   necessary and then closed. This can happen many times during the
%   simulation of a model.
%
% 1 Always Open Strategy:
%   In this case we have a more sophisticated management of slave processes,
%   which are no longer closed at the end of each job. The slave processes
%   wait for a new job (if it exists). If a slave does not receive a new job after a
%   fixed time it is destroyed. This solution removes the computational
%   time necessary to Open/Close new Matlab instances.
%
% The first (point 0) is the default Strategy
% i.e.(Parallel_info.leaveSlaveOpen=0). This value can be changed by the
% user in xxx.mod file or it is changed by the programmer if it is necessary to
% reduce the overall computational time. See for example the
% prior_posterior_statistics.m.
%
% The number of parallelized threads will be equal to (nBlock-fBlock+1).
%
% Treatment of global variables:
%   Global variables used within the called function are wrapped and passed by storing their
%   values at the start of the parallel computation in a file via
%   storeGlobalVars.m. This file is then loaded in the separate,
%   independent slave Matlab sessions. By keeping them separate, no
%   interaction via global variables can take place.
%
% INPUTS
%  o Parallel [struct vector]   copy of options_.parallel
%  o fBlock [int]               index number of the first thread
%                               (between 1 and nBlock)
%  o nBlock [int]               index number of the last thread
%  o NamFileInput [cell array]  contains the list of input files to be
%                               copied in the working directory of remote slaves
%                               2 columns, as many lines as there are files
%                               - first column contains directory paths
%                               - second column contains filenames
%  o fname [string]             name of the function to be parallelized, and
%                               which will be run on the slaves
%  o fInputVar [struct]         structure containing local variables to be used
%                               by fName on the slaves
%  o fGlobalVar [struct]        structure containing global variables to be used
%                               by fName on the slaves
%  o Parallel_info              []
%  o initialize                 []
%
% OUTPUT
%  o fOutVar [struct vector]   result of the parallel computation, one
%                              struct per thread
%  o nBlockPerCPU [int vector] for each CPU used, indicates the number of
%                              threads run on that CPU
%  o totCPU [int]              total number of CPUs used (can be lower than
%                              the number of CPUs declared in "Parallel", if
%                              the number of required threads is lower)

% Copyright © 2009-2017 Dynare Team
%
% This file is part of Dynare.
%
% Dynare is free software: you can redistribute it and/or modify
% it under the terms of the GNU General Public License as published by