blob: 98f027cee4013ac4f75db7a4ade31c8d5f8056fa [file] [log] [blame]
#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;
}