starpu-max/include/starpu_perfmodel.h

/* StarPU --- Runtime system for heterogeneous multicore architectures.
 *
 * Copyright (C) 2010-2012  Université de Bordeaux 1
 * Copyright (C) 2010, 2011, 2012  Centre National de la Recherche Scientifique
 * Copyright (C) 2011  Télécom-SudParis
 *
 * StarPU is free software; you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as published by
 * the Free Software Foundation; either version 2.1 of the License, or (at
 * your option) any later version.
 *
 * StarPU is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 *
 * See the GNU Lesser General Public License in COPYING.LGPL for more details.
 */

#ifndef __STARPU_PERFMODEL_H__
#define __STARPU_PERFMODEL_H__

#include <starpu.h>
#include <stdio.h>

#include <starpu_util.h>

#if ! defined(_MSC_VER)
#  include <pthread.h>
#endif

#ifdef __cplusplus
extern "C"
{
#endif

struct starpu_task;
struct starpu_buffer_descr;

/*
   it is possible that we have multiple versions of the same kind of workers,
   for instance multiple GPUs or even different CPUs within the same machine
   so we do not use the archtype enum type directly for performance models
*/

enum starpu_perf_archtype
{
	STARPU_CPU_DEFAULT = 0,
	/* CPU combined workers between 0 and STARPU_MAXCPUS-1 */
	STARPU_CUDA_DEFAULT = STARPU_MAXCPUS,
	STARPU_OPENCL_DEFAULT = STARPU_CUDA_DEFAULT + STARPU_MAXCUDADEVS,
	/* STARPU_OPENCL_DEFAULT + devid */
	STARPU_GORDON_DEFAULT = STARPU_OPENCL_DEFAULT + STARPU_MAXOPENCLDEVS
};

#ifdef __STDC_VERSION__
#  if __STDC_VERSION__ > 199901L || STARPU_GNUC_PREREQ(4, 6)

/* Make sure the following assertions hold, since StarPU relies on it.  */

_Static_assert(STARPU_CPU_DEFAULT == 0,
	       "invalid STARPU_CPU_DEFAULT value");
_Static_assert(STARPU_CUDA_DEFAULT > STARPU_CPU_DEFAULT,
	       "invalid STARPU_CPU_DEFAULT value");
_Static_assert(STARPU_CUDA_DEFAULT < STARPU_OPENCL_DEFAULT,
	       "invalid STARPU_{CUDA,OPENCL}_DEFAULT values");

#  endif
#endif

#define STARPU_NARCH_VARIATIONS	(STARPU_GORDON_DEFAULT+1)

struct starpu_perfmodel_history_entry
{
	//double measured;

	/* mean_n = 1/n sum */
	double mean;

	/* n dev_n = sum2 - 1/n (sum)^2 */
	double deviation;

	/* sum of samples */
	double sum;

	/* sum of samples^2 */
	double sum2;

//	/* sum of ln(measured) */
//	double sumlny;
//
//	/* sum of ln(size) */
//	double sumlnx;
//	double sumlnx2;
//
//	/* sum of ln(size) ln(measured) */
//	double sumlnxlny;
//
	unsigned nsample;

	uint32_t footprint;
#ifdef STARPU_HAVE_WINDOWS
	unsigned size; /* in bytes */
#else
	size_t size; /* in bytes */
#endif
};

struct starpu_perfmodel_history_list
{
	struct starpu_perfmodel_history_list *next;
	struct starpu_perfmodel_history_entry *entry;
};

struct starpu_perfmodel_regression_model
{
	/* sum of ln(measured) */
	double sumlny;

	/* sum of ln(size) */
	double sumlnx;
	double sumlnx2;

	/* minimum/maximum(size) */
	unsigned long minx;
	unsigned long maxx;

	/* sum of ln(size) ln(measured) */
	double sumlnxlny;

	/* y = alpha size ^ beta */
	double alpha;
	double beta;
	unsigned valid;

	/* y = a size ^b + c */
	double a, b, c;
	unsigned nl_valid;

	unsigned nsample;
};

struct starpu_perfmodel_history_table;

#define starpu_per_arch_perfmodel starpu_perfmodel_per_arch STARPU_DEPRECATED

struct starpu_perfmodel_per_arch
{
	double (*cost_model)(struct starpu_buffer_descr *t) STARPU_DEPRECATED; /* returns expected duration in µs */
	double (*cost_function)(struct starpu_task *task, enum starpu_perf_archtype arch, unsigned nimpl); /* returns expected duration in µs */
	size_t (*size_base)(struct starpu_task *, enum starpu_perf_archtype arch, unsigned nimpl);

	/* internal variables */
	struct starpu_perfmodel_history_table *history;
	struct starpu_perfmodel_history_list *list;
	struct starpu_perfmodel_regression_model regression;
#ifdef STARPU_MODEL_DEBUG
	char debug_path[256];
#endif
};

enum starpu_perfmodel_type
{
	STARPU_PER_ARCH,	/* Application-provided per-arch cost model function */
	STARPU_COMMON,		/* Application-provided common cost model function, with per-arch factor */
	STARPU_HISTORY_BASED,	/* Automatic history-based cost model */
	STARPU_REGRESSION_BASED,	/* Automatic linear regression-based cost model  (alpha * size ^ beta) */
	STARPU_NL_REGRESSION_BASED	/* Automatic non-linear regression-based cost model (a * size ^ b + c) */
};

struct starpu_perfmodel
{
	/* which model is used for that task ? */
	enum starpu_perfmodel_type type;

	/* single cost model (STARPU_COMMON), returns expected duration in µs */
	double (*cost_model)(struct starpu_buffer_descr *) STARPU_DEPRECATED;
	double (*cost_function)(struct starpu_task *, unsigned nimpl);

	size_t (*size_base)(struct starpu_task *, unsigned nimpl);

	/* per-architecture model */
	struct starpu_perfmodel_per_arch per_arch[STARPU_NARCH_VARIATIONS][STARPU_MAXIMPLEMENTATIONS];

	/* Name of the performance model, this is used as a file name when saving history-based performance models */
	const char *symbol;

	/* Internal variables */
	unsigned is_loaded;
	unsigned benchmarking;

#if defined(_MSC_VER)
	void *model_rwlock;
#else
	pthread_rwlock_t model_rwlock;
#endif
};

enum starpu_perf_archtype starpu_worker_get_perf_archtype(int workerid);

/* This function is intended to be used by external tools that should read the
 * performance model files */
int starpu_perfmodel_load_symbol(const char *symbol, struct starpu_perfmodel *model);
void starpu_perfmodel_debugfilepath(struct starpu_perfmodel *model, enum starpu_perf_archtype arch, char *path, size_t maxlen, unsigned nimpl);
void starpu_perfmodel_get_arch_name(enum starpu_perf_archtype arch, char *archname, size_t maxlen, unsigned nimpl);

int starpu_perfmodel_list(FILE *output);
void starpu_perfmodel_print(struct starpu_perfmodel *model, enum starpu_perf_archtype arch, unsigned nimpl, char *parameter, uint32_t *footprint, FILE *output);
int starpu_perfmodel_print_all(struct starpu_perfmodel *model, char *arch, char *parameter, uint32_t *footprint, FILE *output);

void starpu_perfmodel_update_history(struct starpu_perfmodel *model, struct starpu_task *task, enum starpu_perf_archtype arch, unsigned cpuid, unsigned nimpl, double measured);

void starpu_bus_print_bandwidth(FILE *f);
void starpu_bus_print_affinity(FILE *f);

#ifdef __cplusplus
}
#endif

#endif /* __STARPU_PERFMODEL_H__ */