steadystate.c - platform/external/fio - Git at Google

 #include <stdlib.h>

 #include "fio.h"
 #include "steadystate.h"
 #include "helper_thread.h"

 bool steadystate_enabled = false;

 static void steadystate_alloc(struct thread_data *td)
 {
 	td->ss.bw_data = calloc(td->ss.dur, sizeof(uint64_t));
 	td->ss.iops_data = calloc(td->ss.dur, sizeof(uint64_t));

 	td->ss.state |= __FIO_SS_DATA;
 }

 void steadystate_setup(void)
 {
 	int i, prev_groupid;
 	struct thread_data *td, *prev_td;

 	if (!steadystate_enabled)
 		return;

 	/*
 	 * if group reporting is enabled, identify the last td
 	 * for each group and use it for storing steady state
 	 * data
 	 */
 	prev_groupid = -1;
 	prev_td = NULL;
 	for_each_td(td, i) {
 		if (!td->ss.dur)
 			continue;

 		if (!td->o.group_reporting) {
 			steadystate_alloc(td);
 			continue;
 		}

 		if (prev_groupid != td->groupid) {
 			if (prev_td != NULL) {
 				steadystate_alloc(prev_td);
 			}
 			prev_groupid = td->groupid;
 		}
 		prev_td = td;
 	}

 	if (prev_td != NULL && prev_td->o.group_reporting) {
 		steadystate_alloc(prev_td);
 	}
 }

 static bool steadystate_slope(uint64_t iops, uint64_t bw,
 			      struct thread_data *td)
 {
 	int i, j;
 	double result;
 	struct steadystate_data *ss = &td->ss;
 	uint64_t new_val;

 	ss->bw_data[ss->tail] = bw;
 	ss->iops_data[ss->tail] = iops;

 	if (ss->state & __FIO_SS_IOPS)
 		new_val = iops;
 	else
 		new_val = bw;

 	if (ss->state & __FIO_SS_BUFFER_FULL || ss->tail - ss->head == ss->dur - 1) {
 		if (!(ss->state & __FIO_SS_BUFFER_FULL)) {
 			/* first time through */
 			for(i = 0, ss->sum_y = 0; i < ss->dur; i++) {
 				if (ss->state & __FIO_SS_IOPS)
 					ss->sum_y += ss->iops_data[i];
 				else
 					ss->sum_y += ss->bw_data[i];
 				j = (ss->head + i) % ss->dur;
 				if (ss->state & __FIO_SS_IOPS)
 					ss->sum_xy += i * ss->iops_data[j];
 				else
 					ss->sum_xy += i * ss->bw_data[j];
 			}
 			ss->state |= __FIO_SS_BUFFER_FULL;
 		} else {		/* easy to update the sums */
 			ss->sum_y -= ss->oldest_y;
 			ss->sum_y += new_val;
 			ss->sum_xy = ss->sum_xy - ss->sum_y + ss->dur * new_val;
 		}

 		if (ss->state & __FIO_SS_IOPS)
 			ss->oldest_y = ss->iops_data[ss->head];
 		else
 			ss->oldest_y = ss->bw_data[ss->head];

 		/*
 		 * calculate slope as (sum_xy - sum_x * sum_y / n) / (sum_(x^2)
 		 * - (sum_x)^2 / n) This code assumes that all x values are
 		 * equally spaced when they are often off by a few milliseconds.
 		 * This assumption greatly simplifies the calculations.
 		 */
 		ss->slope = (ss->sum_xy - (double) ss->sum_x * ss->sum_y / ss->dur) /
 				(ss->sum_x_sq - (double) ss->sum_x * ss->sum_x / ss->dur);
 		if (ss->state & __FIO_SS_PCT)
 			ss->criterion = 100.0 * ss->slope / (ss->sum_y / ss->dur);
 		else
 			ss->criterion = ss->slope;

 		dprint(FD_STEADYSTATE, "sum_y: %llu, sum_xy: %llu, slope: %f, "
 					"criterion: %f, limit: %f\n",
 					(unsigned long long) ss->sum_y,
 					(unsigned long long) ss->sum_xy,
 					ss->slope, ss->criterion, ss->limit);

 		result = ss->criterion * (ss->criterion < 0.0 ? -1.0 : 1.0);
 		if (result < ss->limit)
 			return true;
 	}

 	ss->tail = (ss->tail + 1) % ss->dur;
 	if (ss->tail <= ss->head)
 		ss->head = (ss->head + 1) % ss->dur;

 	return false;
 }

 static bool steadystate_deviation(uint64_t iops, uint64_t bw,
 				  struct thread_data *td)
 {
 	int i;
 	double diff;
 	double mean;

 	struct steadystate_data *ss = &td->ss;

 	ss->bw_data[ss->tail] = bw;
 	ss->iops_data[ss->tail] = iops;

 	if (ss->state & __FIO_SS_BUFFER_FULL || ss->tail - ss->head == ss->dur - 1) {
 		if (!(ss->state & __FIO_SS_BUFFER_FULL)) {
 			/* first time through */
 			for(i = 0, ss->sum_y = 0; i < ss->dur; i++)
 				if (ss->state & __FIO_SS_IOPS)
 					ss->sum_y += ss->iops_data[i];
 				else
 					ss->sum_y += ss->bw_data[i];
 			ss->state |= __FIO_SS_BUFFER_FULL;
 		} else {		/* easy to update the sum */
 			ss->sum_y -= ss->oldest_y;
 			if (ss->state & __FIO_SS_IOPS)
 				ss->sum_y += ss->iops_data[ss->tail];
 			else
 				ss->sum_y += ss->bw_data[ss->tail];
 		}

 		if (ss->state & __FIO_SS_IOPS)
 			ss->oldest_y = ss->iops_data[ss->head];
 		else
 			ss->oldest_y = ss->bw_data[ss->head];

 		mean = (double) ss->sum_y / ss->dur;
 		ss->deviation = 0.0;

 		for (i = 0; i < ss->dur; i++) {
 			if (ss->state & __FIO_SS_IOPS)
 				diff = ss->iops_data[i] - mean;
 			else
 				diff = ss->bw_data[i] - mean;
 			ss->deviation = max(ss->deviation, diff * (diff < 0.0 ? -1.0 : 1.0));
 		}

 		if (ss->state & __FIO_SS_PCT)
 			ss->criterion = 100.0 * ss->deviation / mean;
 		else
 			ss->criterion = ss->deviation;

 		dprint(FD_STEADYSTATE, "sum_y: %llu, mean: %f, max diff: %f, "
 					"objective: %f, limit: %f\n",
 					(unsigned long long) ss->sum_y, mean,
 					ss->deviation, ss->criterion, ss->limit);

 		if (ss->criterion < ss->limit)
 			return true;
 	}

 	ss->tail = (ss->tail + 1) % ss->dur;
 	if (ss->tail <= ss->head)
 		ss->head = (ss->head + 1) % ss->dur;

 	return false;
 }

 void steadystate_check(void)
 {
 	int i, j, ddir, prev_groupid, group_ramp_time_over = 0;
 	unsigned long rate_time;
 	struct thread_data *td, *td2;
 	struct timeval now;
 	uint64_t group_bw = 0, group_iops = 0;
 	uint64_t td_iops, td_bytes;
 	bool ret;

 	prev_groupid = -1;
 	for_each_td(td, i) {
 		struct steadystate_data *ss = &td->ss;

 		if (!ss->dur || td->runstate <= TD_SETTING_UP ||
 		    td->runstate >= TD_EXITED || !ss->state ||
 		    ss->state & __FIO_SS_ATTAINED)
 			continue;

 		td_iops = 0;
 		td_bytes = 0;
 		if (!td->o.group_reporting ||
 		    (td->o.group_reporting && td->groupid != prev_groupid)) {
 			group_bw = 0;
 			group_iops = 0;
 			group_ramp_time_over = 0;
 		}
 		prev_groupid = td->groupid;

 		fio_gettime(&now, NULL);
 		if (ss->ramp_time && !(ss->state & __FIO_SS_RAMP_OVER)) {
 			/*
 			 * Begin recording data one second after ss->ramp_time
 			 * has elapsed
 			 */
 			if (utime_since(&td->epoch, &now) >= (ss->ramp_time + 1000000L))
 				ss->state |= __FIO_SS_RAMP_OVER;
 		}

 		td_io_u_lock(td);
 		for (ddir = 0; ddir < DDIR_RWDIR_CNT; ddir++) {
 			td_iops += td->io_blocks[ddir];
 			td_bytes += td->io_bytes[ddir];
 		}
 		td_io_u_unlock(td);

 		rate_time = mtime_since(&ss->prev_time, &now);
 		memcpy(&ss->prev_time, &now, sizeof(now));

 		/*
 		 * Begin monitoring when job starts but don't actually use
 		 * data in checking stopping criterion until ss->ramp_time is
 		 * over. This ensures that we will have a sane value in
 		 * prev_iops/bw the first time through after ss->ramp_time
 		 * is done.
 		 */
 		if (ss->state & __FIO_SS_RAMP_OVER) {
 			group_bw += 1000 * (td_bytes - ss->prev_bytes) / rate_time;
 			group_iops += 1000 * (td_iops - ss->prev_iops) / rate_time;
 			++group_ramp_time_over;
 		}
 		ss->prev_iops = td_iops;
 		ss->prev_bytes = td_bytes;

 		if (td->o.group_reporting && !(ss->state & __FIO_SS_DATA))
 			continue;

 		/*
 		 * Don't begin checking criterion until ss->ramp_time is over
 		 * for at least one thread in group
 		 */
 		if (!group_ramp_time_over)
 			continue;

 		dprint(FD_STEADYSTATE, "steadystate_check() thread: %d, "
 					"groupid: %u, rate_msec: %ld, "
 					"iops: %llu, bw: %llu, head: %d, tail: %d\n",
 					i, td->groupid, rate_time,
 					(unsigned long long) group_iops,
 					(unsigned long long) group_bw,
 					ss->head, ss->tail);

 		if (ss->state & __FIO_SS_SLOPE)
 			ret = steadystate_slope(group_iops, group_bw, td);
 		else
 			ret = steadystate_deviation(group_iops, group_bw, td);

 		if (ret) {
 			if (td->o.group_reporting) {
 				for_each_td(td2, j) {
 					if (td2->groupid == td->groupid) {
 						td2->ss.state |= __FIO_SS_ATTAINED;
 						fio_mark_td_terminate(td2);
 					}
 				}
 			} else {
 				ss->state |= __FIO_SS_ATTAINED;
 				fio_mark_td_terminate(td);
 			}
 		}
 	}
 }

 int td_steadystate_init(struct thread_data *td)
 {
 	struct steadystate_data *ss = &td->ss;
 	struct thread_options *o = &td->o;
 	struct thread_data *td2;
 	int j;

 	memset(ss, 0, sizeof(*ss));

 	if (o->ss_dur) {
 		steadystate_enabled = true;
 		o->ss_dur /= 1000000L;

 		/* put all steady state info in one place */
 		ss->dur = o->ss_dur;
 		ss->limit = o->ss_limit.u.f;
 		ss->ramp_time = o->ss_ramp_time;

 		ss->state = o->ss_state;
 		if (!td->ss.ramp_time)
 			ss->state |= __FIO_SS_RAMP_OVER;

 		ss->sum_x = o->ss_dur * (o->ss_dur - 1) / 2;
 		ss->sum_x_sq = (o->ss_dur - 1) * (o->ss_dur) * (2*o->ss_dur - 1) / 6;
 	}

 	/* make sure that ss options are consistent within reporting group */
 	for_each_td(td2, j) {
 		if (td2->groupid == td->groupid) {
 			struct steadystate_data *ss2 = &td2->ss;

 			if (ss2->dur != ss->dur ||
 			    ss2->limit != ss->limit ||
 			    ss2->ramp_time != ss->ramp_time ||
 			    ss2->state != ss->state ||
 			    ss2->sum_x != ss->sum_x ||
 			    ss2->sum_x_sq != ss->sum_x_sq) {
 				td_verror(td, EINVAL, "job rejected: steadystate options must be consistent within reporting groups");
 				return 1;
 			}
 		}
 	}

 	return 0;
 }

 uint64_t steadystate_bw_mean(struct thread_stat *ts)
 {
 	int i;
 	uint64_t sum;

 	for (i = 0, sum = 0; i < ts->ss_dur; i++)
 		sum += ts->ss_bw_data[i];

 	return sum / ts->ss_dur;
 }

 uint64_t steadystate_iops_mean(struct thread_stat *ts)
 {
 	int i;
 	uint64_t sum;

 	for (i = 0, sum = 0; i < ts->ss_dur; i++)
 		sum += ts->ss_iops_data[i];

 	return sum / ts->ss_dur;
 }
	#include <stdlib.h>

	#include "fio.h"
	#include "steadystate.h"
	#include "helper_thread.h"

	bool steadystate_enabled = false;

	static void steadystate_alloc(struct thread_data *td)
	{
	td->ss.bw_data = calloc(td->ss.dur, sizeof(uint64_t));
	td->ss.iops_data = calloc(td->ss.dur, sizeof(uint64_t));

	td->ss.state \|= __FIO_SS_DATA;
	}

	void steadystate_setup(void)
	{
	int i, prev_groupid;
	struct thread_data td, prev_td;

	if (!steadystate_enabled)
	return;

	/*
	* if group reporting is enabled, identify the last td
	* for each group and use it for storing steady state
	* data
	*/
	prev_groupid = -1;
	prev_td = NULL;
	for_each_td(td, i) {
	if (!td->ss.dur)
	continue;

	if (!td->o.group_reporting) {
	steadystate_alloc(td);
	continue;
	}

	if (prev_groupid != td->groupid) {
	if (prev_td != NULL) {
	steadystate_alloc(prev_td);
	}
	prev_groupid = td->groupid;
	}
	prev_td = td;
	}

	if (prev_td != NULL && prev_td->o.group_reporting) {
	steadystate_alloc(prev_td);
	}
	}

	static bool steadystate_slope(uint64_t iops, uint64_t bw,
	struct thread_data *td)
	{
	int i, j;
	double result;
	struct steadystate_data *ss = &td->ss;
	uint64_t new_val;

	ss->bw_data[ss->tail] = bw;
	ss->iops_data[ss->tail] = iops;

	if (ss->state & __FIO_SS_IOPS)
	new_val = iops;
	else
	new_val = bw;

	if (ss->state & __FIO_SS_BUFFER_FULL \|\| ss->tail - ss->head == ss->dur - 1) {
	if (!(ss->state & __FIO_SS_BUFFER_FULL)) {
	/* first time through */
	for(i = 0, ss->sum_y = 0; i < ss->dur; i++) {
	if (ss->state & __FIO_SS_IOPS)
	ss->sum_y += ss->iops_data[i];
	else
	ss->sum_y += ss->bw_data[i];
	j = (ss->head + i) % ss->dur;
	if (ss->state & __FIO_SS_IOPS)
	ss->sum_xy += i * ss->iops_data[j];
	else
	ss->sum_xy += i * ss->bw_data[j];
	}
	ss->state \|= __FIO_SS_BUFFER_FULL;
	} else { /* easy to update the sums */
	ss->sum_y -= ss->oldest_y;
	ss->sum_y += new_val;
	ss->sum_xy = ss->sum_xy - ss->sum_y + ss->dur * new_val;
	}

	if (ss->state & __FIO_SS_IOPS)
	ss->oldest_y = ss->iops_data[ss->head];
	else
	ss->oldest_y = ss->bw_data[ss->head];

	/*
	* calculate slope as (sum_xy - sum_x * sum_y / n) / (sum_(x^2)
	* - (sum_x)^2 / n) This code assumes that all x values are
	* equally spaced when they are often off by a few milliseconds.
	* This assumption greatly simplifies the calculations.
	*/
	ss->slope = (ss->sum_xy - (double) ss->sum_x * ss->sum_y / ss->dur) /
	(ss->sum_x_sq - (double) ss->sum_x * ss->sum_x / ss->dur);
	if (ss->state & __FIO_SS_PCT)
	ss->criterion = 100.0 * ss->slope / (ss->sum_y / ss->dur);
	else
	ss->criterion = ss->slope;

	dprint(FD_STEADYSTATE, "sum_y: %llu, sum_xy: %llu, slope: %f, "
	"criterion: %f, limit: %f\n",
	(unsigned long long) ss->sum_y,
	(unsigned long long) ss->sum_xy,
	ss->slope, ss->criterion, ss->limit);

	result = ss->criterion * (ss->criterion < 0.0 ? -1.0 : 1.0);
	if (result < ss->limit)
	return true;
	}

	ss->tail = (ss->tail + 1) % ss->dur;
	if (ss->tail <= ss->head)
	ss->head = (ss->head + 1) % ss->dur;

	return false;
	}

	static bool steadystate_deviation(uint64_t iops, uint64_t bw,
	struct thread_data *td)
	{
	int i;
	double diff;
	double mean;

	struct steadystate_data *ss = &td->ss;

	ss->bw_data[ss->tail] = bw;
	ss->iops_data[ss->tail] = iops;

	if (ss->state & __FIO_SS_BUFFER_FULL \|\| ss->tail - ss->head == ss->dur - 1) {
	if (!(ss->state & __FIO_SS_BUFFER_FULL)) {
	/* first time through */
	for(i = 0, ss->sum_y = 0; i < ss->dur; i++)
	if (ss->state & __FIO_SS_IOPS)
	ss->sum_y += ss->iops_data[i];
	else
	ss->sum_y += ss->bw_data[i];
	ss->state \|= __FIO_SS_BUFFER_FULL;
	} else { /* easy to update the sum */
	ss->sum_y -= ss->oldest_y;
	if (ss->state & __FIO_SS_IOPS)
	ss->sum_y += ss->iops_data[ss->tail];
	else
	ss->sum_y += ss->bw_data[ss->tail];
	}

	if (ss->state & __FIO_SS_IOPS)
	ss->oldest_y = ss->iops_data[ss->head];
	else
	ss->oldest_y = ss->bw_data[ss->head];

	mean = (double) ss->sum_y / ss->dur;
	ss->deviation = 0.0;

	for (i = 0; i < ss->dur; i++) {
	if (ss->state & __FIO_SS_IOPS)
	diff = ss->iops_data[i] - mean;
	else
	diff = ss->bw_data[i] - mean;
	ss->deviation = max(ss->deviation, diff * (diff < 0.0 ? -1.0 : 1.0));
	}

	if (ss->state & __FIO_SS_PCT)
	ss->criterion = 100.0 * ss->deviation / mean;
	else
	ss->criterion = ss->deviation;

	dprint(FD_STEADYSTATE, "sum_y: %llu, mean: %f, max diff: %f, "
	"objective: %f, limit: %f\n",
	(unsigned long long) ss->sum_y, mean,
	ss->deviation, ss->criterion, ss->limit);

	if (ss->criterion < ss->limit)
	return true;
	}

	ss->tail = (ss->tail + 1) % ss->dur;
	if (ss->tail <= ss->head)
	ss->head = (ss->head + 1) % ss->dur;

	return false;
	}

	void steadystate_check(void)
	{
	int i, j, ddir, prev_groupid, group_ramp_time_over = 0;
	unsigned long rate_time;
	struct thread_data td, td2;
	struct timeval now;
	uint64_t group_bw = 0, group_iops = 0;
	uint64_t td_iops, td_bytes;
	bool ret;

	prev_groupid = -1;
	for_each_td(td, i) {
	struct steadystate_data *ss = &td->ss;

	if (!ss->dur \|\| td->runstate <= TD_SETTING_UP \|\|
	td->runstate >= TD_EXITED \|\| !ss->state \|\|
	ss->state & __FIO_SS_ATTAINED)
	continue;

	td_iops = 0;
	td_bytes = 0;
	if (!td->o.group_reporting \|\|
	(td->o.group_reporting && td->groupid != prev_groupid)) {
	group_bw = 0;
	group_iops = 0;
	group_ramp_time_over = 0;
	}
	prev_groupid = td->groupid;

	fio_gettime(&now, NULL);
	if (ss->ramp_time && !(ss->state & __FIO_SS_RAMP_OVER)) {
	/*
	* Begin recording data one second after ss->ramp_time
	* has elapsed
	*/
	if (utime_since(&td->epoch, &now) >= (ss->ramp_time + 1000000L))
	ss->state \|= __FIO_SS_RAMP_OVER;
	}

	td_io_u_lock(td);
	for (ddir = 0; ddir < DDIR_RWDIR_CNT; ddir++) {
	td_iops += td->io_blocks[ddir];
	td_bytes += td->io_bytes[ddir];
	}
	td_io_u_unlock(td);

	rate_time = mtime_since(&ss->prev_time, &now);
	memcpy(&ss->prev_time, &now, sizeof(now));

	/*
	* Begin monitoring when job starts but don't actually use
	* data in checking stopping criterion until ss->ramp_time is
	* over. This ensures that we will have a sane value in
	* prev_iops/bw the first time through after ss->ramp_time
	* is done.
	*/
	if (ss->state & __FIO_SS_RAMP_OVER) {
	group_bw += 1000 * (td_bytes - ss->prev_bytes) / rate_time;
	group_iops += 1000 * (td_iops - ss->prev_iops) / rate_time;
	++group_ramp_time_over;
	}
	ss->prev_iops = td_iops;
	ss->prev_bytes = td_bytes;

	if (td->o.group_reporting && !(ss->state & __FIO_SS_DATA))
	continue;

	/*
	* Don't begin checking criterion until ss->ramp_time is over
	* for at least one thread in group
	*/
	if (!group_ramp_time_over)
	continue;

	dprint(FD_STEADYSTATE, "steadystate_check() thread: %d, "
	"groupid: %u, rate_msec: %ld, "
	"iops: %llu, bw: %llu, head: %d, tail: %d\n",
	i, td->groupid, rate_time,
	(unsigned long long) group_iops,
	(unsigned long long) group_bw,
	ss->head, ss->tail);

	if (ss->state & __FIO_SS_SLOPE)
	ret = steadystate_slope(group_iops, group_bw, td);
	else
	ret = steadystate_deviation(group_iops, group_bw, td);

	if (ret) {
	if (td->o.group_reporting) {
	for_each_td(td2, j) {
	if (td2->groupid == td->groupid) {
	td2->ss.state \|= __FIO_SS_ATTAINED;
	fio_mark_td_terminate(td2);
	}
	}
	} else {
	ss->state \|= __FIO_SS_ATTAINED;
	fio_mark_td_terminate(td);
	}
	}
	}
	}

	int td_steadystate_init(struct thread_data *td)
	{
	struct steadystate_data *ss = &td->ss;
	struct thread_options *o = &td->o;
	struct thread_data *td2;
	int j;

	memset(ss, 0, sizeof(*ss));

	if (o->ss_dur) {
	steadystate_enabled = true;
	o->ss_dur /= 1000000L;

	/* put all steady state info in one place */
	ss->dur = o->ss_dur;
	ss->limit = o->ss_limit.u.f;
	ss->ramp_time = o->ss_ramp_time;

	ss->state = o->ss_state;
	if (!td->ss.ramp_time)
	ss->state \|= __FIO_SS_RAMP_OVER;

	ss->sum_x = o->ss_dur * (o->ss_dur - 1) / 2;
	ss->sum_x_sq = (o->ss_dur - 1) * (o->ss_dur) * (2*o->ss_dur - 1) / 6;
	}

	/* make sure that ss options are consistent within reporting group */
	for_each_td(td2, j) {
	if (td2->groupid == td->groupid) {
	struct steadystate_data *ss2 = &td2->ss;

	if (ss2->dur != ss->dur \|\|
	ss2->limit != ss->limit \|\|
	ss2->ramp_time != ss->ramp_time \|\|
	ss2->state != ss->state \|\|
	ss2->sum_x != ss->sum_x \|\|
	ss2->sum_x_sq != ss->sum_x_sq) {
	td_verror(td, EINVAL, "job rejected: steadystate options must be consistent within reporting groups");
	return 1;
	}
	}
	}

	return 0;
	}

	uint64_t steadystate_bw_mean(struct thread_stat *ts)
	{
	int i;
	uint64_t sum;

	for (i = 0, sum = 0; i < ts->ss_dur; i++)
	sum += ts->ss_bw_data[i];

	return sum / ts->ss_dur;
	}

	uint64_t steadystate_iops_mean(struct thread_stat *ts)
	{
	int i;
	uint64_t sum;

	for (i = 0, sum = 0; i < ts->ss_dur; i++)
	sum += ts->ss_iops_data[i];

	return sum / ts->ss_dur;
	}