From def62837cdeac53fb41fc2fcf8e9fb357caa9568 Mon Sep 17 00:00:00 2001 From: velho Date: Sat, 21 Apr 2007 13:47:07 +0000 Subject: [PATCH] Cleaning up the lagrange model. git-svn-id: svn+ssh://scm.gforge.inria.fr/svn/simgrid/simgrid/trunk@3439 48e7efb5-ca39-0410-a469-dd3cf9ba447f --- src/surf/lagrange.c | 380 ++++++++++++++++++++++---------------------- 1 file changed, 188 insertions(+), 192 deletions(-) diff --git a/src/surf/lagrange.c b/src/surf/lagrange.c index 01e22449c2..c70af9e1f9 100644 --- a/src/surf/lagrange.c +++ b/src/surf/lagrange.c @@ -20,66 +20,60 @@ #include #endif -#define LAMBDA_STEP 0.01 +XBT_LOG_NEW_DEFAULT_SUBCATEGORY(surf_lagrange, surf, "Logging specific to SURF (lagrange)"); -XBT_LOG_NEW_DEFAULT_SUBCATEGORY(surf_lagrange, surf, - "Logging specific to SURF (lagrange)"); -XBT_LOG_NEW_SUBCATEGORY(surf_writelambda, surf, - "Generates the lambda.in file. WARNING: the size of this file might be a few GBs."); +/* + * Local prototypes to implement the lagrangian optimization with optimal step, also called dicotomi. + */ +//solves the proportional fairness using a lagrange optimizition with dicotomi step +void lagrange_solve (lmm_system_t sys); +//computes the value of the dicotomi using a initial values, init, with a specific variable or constraint +double dicotomi(double init, double diff(double, void*), void *var_cnst, double min_error); +//computes the value of the differential of variable param_var applied to mu +double partial_diff_mu (double mu, void * param_var); +//computes the value of the differential of constraint param_cnst applied to lambda +double partial_diff_lambda (double lambda, void * param_cnst); + -void lagrange_solve(lmm_system_t sys); void lagrange_solve(lmm_system_t sys) { /* * Lagrange Variables. */ - int max_iterations= 1000000; - double epsilon_min_error = 0.00001; + int max_iterations= 10; + double epsilon_min_error = 1e-10; double overall_error = 1; - double sigma_step = LAMBDA_STEP; - //double capacity_error=0, bound_error=0; - int watch_out = 0; + /* * Variables to manipulate the data structure proposed to model the maxmin * fairness. See docummentation for more details. */ - xbt_swag_t elem_list = NULL; - //lmm_element_t elem = NULL; - lmm_element_t elem1 = NULL; - + xbt_swag_t elem_list = NULL; + lmm_element_t elem = NULL; - xbt_swag_t cnst_list = NULL; - //lmm_constraint_t cnst = NULL; - lmm_constraint_t cnst1 = NULL; - //lmm_constraint_t cnst2 = NULL; + xbt_swag_t cnst_list = NULL; + lmm_constraint_t cnst = NULL; + + xbt_swag_t var_list = NULL; + lmm_variable_t var = NULL; - xbt_swag_t var_list = NULL; - lmm_variable_t var1 = NULL; - lmm_variable_t var2 = NULL; /* * Auxiliar variables. */ int iteration=0; - double mu_partial=0; - double lambda_partial=0; double tmp=0; - int i,j; - FILE *gnuplot_file=NULL; - //char print_buf[1024]; - //char *trace_buf=xbt_malloc0(sizeof(char)); - //double sum; - + int i; + DEBUG0("Iterative method configuration snapshot =====>"); DEBUG1("#### Maximum number of iterations : %d", max_iterations); DEBUG1("#### Minimum error tolerated : %e", epsilon_min_error); - DEBUG1("#### Step : %e", sigma_step); if ( !(sys->modified)) @@ -91,16 +85,16 @@ void lagrange_solve(lmm_system_t sys) */ var_list = &(sys->variable_set); i=0; - xbt_swag_foreach(var1, var_list) { - if((var1->bound < 0.0) || (var1->weight <= 0.0)){ - DEBUG1("#### NOTE var1(%d) is a boundless variable", i); - var1->mu = -1.0; + xbt_swag_foreach(var, var_list) { + if((var->bound > 0.0) || (var->weight <= 0.0)){ + DEBUG1("#### NOTE var(%d) is a boundless variable", i); + var->mu = -1.0; } else{ - var1->mu = 1.0; - var1->new_mu = 2.0; + var->mu = 1.0; + var->new_mu = 2.0; } - DEBUG2("#### var1(%d)->mu: %e", i, var1->mu); - DEBUG2("#### var1(%d)->weight: %e", i, var1->weight); + DEBUG2("#### var(%d)->mu : %e", i, var->mu); + DEBUG2("#### var(%d)->weight: %e", i, var->weight); i++; } @@ -108,112 +102,39 @@ void lagrange_solve(lmm_system_t sys) * Initialize lambda. */ cnst_list=&(sys->active_constraint_set); - xbt_swag_foreach(cnst1, cnst_list) { - cnst1->lambda = 1.0; - cnst1->new_lambda = 2.0; - DEBUG2("#### cnst1(%p)->lambda: %e", cnst1, cnst1->lambda); - } - - if(XBT_LOG_ISENABLED(surf_writelambda, xbt_log_priority_debug)) { - gnuplot_file = fopen("lambda.in", "w"); - fprintf(gnuplot_file, "# iteration lambda1 lambda2 lambda3 ... lambdaP\n"); + xbt_swag_foreach(cnst, cnst_list) { + cnst->lambda = 1.0; + cnst->new_lambda = 2.0; + DEBUG2("#### cnst(%p)->lambda : %e", cnst, cnst->lambda); } - /* * While doesn't reach a minimun error or a number maximum of iterations. */ while(overall_error > epsilon_min_error && iteration < max_iterations){ + iteration++; - - /* d Dual - * Compute the value of ----------- (\lambda^k, \mu^k) this portion - * d \mu_i^k - * of code depends on function f(x). + + /* + * Compute the value of mu_i */ var_list = &(sys->variable_set); - xbt_swag_foreach(var1, var_list) { - mu_partial = 0; - if((var1->bound >= 0) && (var1->weight > 0) ){ - //for each link with capacity cnsts[i] that uses flow of variable var1 do - for(i=0; icnsts_number; i++) - mu_partial += (var1->cnsts[i].constraint)->lambda + var1->mu; - - mu_partial = -1.0 / mu_partial + var1->bound; - var1->new_mu = var1->mu - sigma_step * mu_partial; - - if(var1->new_mu < 0){ - var1->new_mu = 0; - } + //forall mu_i in mu_1, mu_2, ..., mu_n + xbt_swag_foreach(var, var_list) { + if((var->bound >= 0) && (var->weight > 0) ){ + var->mu = dicotomi(var->mu, partial_diff_mu, var, epsilon_min_error); + if(var->mu < 0) var->mu = 0; } } + - - /* d Dual - * Compute the value of ------------- (\lambda^k, \mu^k) this portion - * d \lambda_i^k - * of code depends on function f(x). + /* + * Compute the value of lambda_i */ - j=0; - if(XBT_LOG_ISENABLED(surf_writelambda, xbt_log_priority_debug)) { - fprintf(gnuplot_file, "\n%d",iteration); - } - xbt_swag_foreach(cnst1, cnst_list) { - j++; - - lambda_partial = 0; - - elem_list = &(cnst1->element_set); - watch_out=0; - xbt_swag_foreach(elem1, elem_list) { - - var2 = elem1->variable; - - if(var2->weight<=0) continue; - - tmp = 0; - - for(i=0; icnsts_number; i++){ - tmp += (var2->cnsts[i].constraint)->lambda; - } - if(var2->bound > 0) - tmp += var2->mu; - - - if(tmp==0) break; - - if (tmp==cnst1->lambda) - watch_out=1; - lambda_partial += (-1.0 / tmp); - } - - if(tmp == 0) - cnst1->new_lambda = LAMBDA_STEP; - else { - lambda_partial += cnst1->bound; - if(watch_out && (lambda_partial>0)) { - /* INFO6("Watch Out (%d) %p! lambda_partial: %e; lambda : %e ; (%e %e) \n",iteration, cnst1, */ - /* lambda_partial, cnst1->lambda, cnst1->lambda / 2, */ - /* cnst1->lambda - sigma_step * lambda_partial); */ - - if(cnst1->lambda < 0) WARN2("Value of cnst1->lambda(%p) = %e < 0", cnst1, cnst1->lambda); - if((cnst1->lambda - sigma_step * lambda_partial) < 0) WARN1("Value of lambda_new = %e < 0", (cnst1->lambda - sigma_step * lambda_partial)); - - if(cnst1->lambda - sigma_step * lambda_partial < cnst1->lambda / 2) - cnst1->new_lambda = cnst1->lambda / 2; - else - cnst1->new_lambda = cnst1->lambda - sigma_step * lambda_partial; - } else - cnst1->new_lambda = cnst1->lambda - sigma_step * lambda_partial; - if(cnst1->new_lambda < 0){ - cnst1->new_lambda = 0; - } - } - - if(XBT_LOG_ISENABLED(surf_writelambda, xbt_log_priority_debug)) { - fprintf(gnuplot_file, " %e", cnst1->lambda); - } - + //forall lambda_i in lambda_1, lambda_2, ..., lambda_n + xbt_swag_foreach(cnst, cnst_list) { + cnst->lambda = dicotomi(cnst->lambda, partial_diff_lambda, cnst, epsilon_min_error); + if(cnst->lambda < 0) cnst->lambda = 0; } @@ -222,76 +143,66 @@ void lagrange_solve(lmm_system_t sys) * the values of \lambda and \mu. */ overall_error=0; - xbt_swag_foreach(var1, var_list) { - if(var1->weight <=0) - var1->value = 0.0; + DEBUG1("Iteration %d ", iteration); + xbt_swag_foreach(var, var_list) { + if(var->weight <=0) + var->value = 0.0; else { tmp = 0; - for(i=0; icnsts_number; i++){ - tmp += (var1->cnsts[i].constraint)->lambda; - if(var1->bound > 0) - tmp+=var1->mu; + for(i=0; icnsts_number; i++){ + tmp += (var->cnsts[i].constraint)->lambda; + if(var->bound > 0) + tmp+=var->mu; } //computes de overall_error - if(overall_error < fabs(var1->value - 1.0/tmp)){ - overall_error = fabs(var1->value - 1.0/tmp); + if(overall_error < fabs(var->value - 1.0/tmp)){ + overall_error = fabs(var->value - 1.0/tmp); } - var1->value = 1.0 / tmp; + var->value = 1.0 / tmp; } - - } - /* Updating lambda's and mu's */ - xbt_swag_foreach(var1, var_list) - if(!((var1->bound > 0.0) || (var1->weight <= 0.0))) - var1->mu = var1->new_mu; - - - xbt_swag_foreach(cnst1, cnst_list) - cnst1->lambda = cnst1->new_lambda; + DEBUG2("======> value of var (%p) = %e", var, var->value); + } } - - - //verify the KKT property - xbt_swag_foreach(cnst1, cnst_list){ + //verify the KKT property for each link + xbt_swag_foreach(cnst, cnst_list){ tmp = 0; - elem_list = &(cnst1->element_set); - xbt_swag_foreach(elem1, elem_list) { - var1 = elem1->variable; - if(var1->weight<=0) continue; - tmp += var1->value; + elem_list = &(cnst->element_set); + xbt_swag_foreach(elem, elem_list) { + var = elem->variable; + if(var->weight<=0) continue; + tmp += var->value; } - - tmp = tmp - cnst1->bound; - - - if(tmp != 0 || cnst1->lambda != 0){ - WARN4("The link %s(%p) doesn't match the KKT property, value expected (=0) got (lambda=%e) (sum_rho=%e)", (char *)cnst1->id, cnst1, cnst1->lambda, tmp); + + tmp = tmp - cnst->bound; + + + if(tmp != 0 || cnst->lambda != 0){ + WARN4("The link %s(%p) doesn't match the KKT property, value expected (=0) got (lambda=%e) (sum_rho=%e)", (char *)cnst->id, cnst, cnst->lambda, tmp); } - + } - - xbt_swag_foreach(var1, var_list){ - if(var1->bound <= 0 || var1->weight <= 0) continue; + + //verify the KKT property of each flow + xbt_swag_foreach(var, var_list){ + if(var->bound <= 0 || var->weight <= 0) continue; tmp = 0; - tmp = (var1->value - var1->bound); + tmp = (var->value - var->bound); - if(tmp != 0 || var1->mu != 0){ - WARN4("The flow %s(%p) doesn't match the KKT property, value expected (=0) got (lambda=%e) (sum_rho=%e)", (char *)var1->id, var1, var1->mu, tmp); + if(tmp != 0 || var->mu != 0){ + WARN4("The flow %s(%p) doesn't match the KKT property, value expected (=0) got (lambda=%e) (sum_rho=%e)", (char *)var->id, var, var->mu, tmp); } } - - if(overall_error <= epsilon_min_error){ DEBUG1("The method converge in %d iterations.", iteration); }else{ @@ -299,31 +210,116 @@ void lagrange_solve(lmm_system_t sys) } - if(XBT_LOG_ISENABLED(surf_writelambda, xbt_log_priority_debug)) { - fclose(gnuplot_file); + +} + +/* + * Returns a double value corresponding to the result of a dicotomi proccess with + * respect to a given variable/constraint (\mu in the case of a variable or \lambda in + * case of a constraint) and a initial value init. + * + * @param init initial value for \mu or \lambda + * @param diff a function that computes the differential of with respect a \mu or \lambda + * @param var_cnst a pointer to a variable or constraint + * @param min_erro a minimun error tolerated + * + * @return a double correponding to the result of the dicotomial process + */ +double dicotomi(double init, double diff(double, void*), void *var_cnst, double min_error){ + double min, max; + double overall_error; + double middle; + + min = max = init; + overall_error = 1; + + DEBUG0("STARTING DICOTOMI... Debuggin, format used [min, max], [D(min),D(max)]"); + + while(overall_error > min_error){ + DEBUG4("====> [%e, %e] , [%e,%e]", min, max, diff(min, var_cnst), diff(max, var_cnst)); + + if( diff(min, var_cnst) > 0 && diff(max, var_cnst) > 0 ){ + if(min == max){ + min = min / 2.0; + }else{ + max = min; + } + }else if( diff(min, var_cnst) < 0 && diff(max, var_cnst) < 0 ){ + if(min == max){ + max = max * 2.0; + }else{ + min = max; + } + }else if( diff(min, var_cnst) < 0 && diff(max, var_cnst) > 0 ){ + middle = (max + min)/2.0; + + if( diff(middle, var_cnst) < 0 ){ + min = middle; + }else if( diff(middle, var_cnst) > 0 ){ + max = middle; + }else{ + WARN0("Found an optimal solution with 0 error!"); + overall_error = 0; + } + overall_error = fabs(min - max); + }else{ + WARN0("The impossible happened, partial_diff(min) >0 && partial_diff(max) < 0"); + } } + return ((min+max)/2.0); +} +double partial_diff_mu(double mu, void *param_var){ + double mu_partial=0.0; + lmm_variable_t var = (lmm_variable_t)param_var; + int i; + //for each link with capacity cnsts[i] that uses flow of variable var do + for(i=0; icnsts_number; i++) + mu_partial += (var->cnsts[i].constraint)->lambda + mu; + + mu_partial = (-1.0/mu_partial) + var->bound; + return mu_partial; +} -/* /\* */ -/* * Now computes the values of each variable (\rho) based on */ -/* * the values of \lambda and \mu. */ -/* *\/ */ -/* var_list = &(sys->variable_set); */ -/* xbt_swag_foreach(var1, var_list) { */ -/* tmp = 0; */ -/* for(i=0; icnsts_number; i++){ */ -/* elem1 = &(var1->cnsts[i]); */ -/* tmp += (elem1->constraint)->lambda + var1->mu; */ -/* } */ -/* var1->weight = 1 / tmp; */ -/* DEBUG2("var1->weight (id=%s) : %e", (char *)var1->id, var1->weight); */ -/* } */ +double partial_diff_lambda(double lambda, void *param_cnst){ + double tmp=0.0; + int i; + xbt_swag_t elem_list = NULL; + lmm_element_t elem = NULL; + lmm_variable_t var = NULL; + lmm_constraint_t cnst= (lmm_constraint_t) param_cnst; + double lambda_partial=0.0; + elem_list = &(cnst->element_set); + + xbt_swag_foreach(elem, elem_list) { + var = elem->variable; + if(var->weight<=0) continue; + + tmp = 0; + for(i=0; icnsts_number; i++){ + tmp += (var->cnsts[i].constraint)->lambda; + } + + if(var->bound > 0) + tmp += var->mu; + + tmp = tmp - cnst->lambda + lambda; + + //avoid a disaster value of lambda + if(tmp==0) lambda_partial = 10e-8; + + lambda_partial += (-1.0 /tmp); + } + lambda_partial += cnst->bound; + + return lambda_partial; } + -- 2.20.1