static Task* create_parallel(std::string name, int host_nb, const msg_host_t* host_list, double* flops_amount,
double* bytes_amount, void* data);
msg_error_t execute();
static Task* create_parallel(std::string name, int host_nb, const msg_host_t* host_list, double* flops_amount,
double* bytes_amount, void* data);
msg_error_t execute();