inline calculated_number backend_calculate_value_from_stored_data(
RRDSET *st // the chart
, RRDDIM *rd // the dimension
, time_t after // the start timestamp
, time_t before // the end timestamp
, uint32_t options // BACKEND_SOURCE_* bitmap
, time_t *first_timestamp // the first point of the database used in this response
, time_t *last_timestamp // the timestamp that should be reported to backend
) {
RRDHOST *host = st->rrdhost;
// find the edges of the rrd database for this chart
time_t first_t = rrdset_first_entry_t(st);
time_t last_t = rrdset_last_entry_t(st);
time_t update_every = st->update_every;
// step back a little, to make sure we have complete data collection
// for all metrics
after -= update_every * 2;
before -= update_every * 2;
// align the time-frame
after = after - (after % update_every);
before = before - (before % update_every);
// for before, loose another iteration
// the latest point will be reported the next time
before -= update_every;
if(unlikely(after > before))
// this can happen when update_every > before - after
after = before;
if(unlikely(after < first_t))
after = first_t;
if(unlikely(before > last_t))
before = last_t;
if(unlikely(before < first_t || after > last_t)) {
// the chart has not been updated in the wanted timeframe
debug(D_BACKEND, "BACKEND: %s.%s.%s: aligned timeframe %lu to %lu is outside the chart's database range %lu to %lu",
host->hostname, st->id, rd->id,
(unsigned long)after, (unsigned long)before,
(unsigned long)first_t, (unsigned long)last_t
);
return NAN;
}
*first_timestamp = after;
*last_timestamp = before;
size_t counter = 0;
calculated_number sum = 0;
long start_at_slot = rrdset_time2slot(st, before),
stop_at_slot = rrdset_time2slot(st, after),
slot, stop_now = 0;
for(slot = start_at_slot; !stop_now ; slot--) {
if(unlikely(slot < 0)) slot = st->entries - 1;
if(unlikely(slot == stop_at_slot)) stop_now = 1;
storage_number n = rd->values[slot];
if(unlikely(!does_storage_number_exist(n))) {
// not collected
continue;
}
calculated_number value = unpack_storage_number(n);
sum += value;
counter++;
}
if(unlikely(!counter)) {
debug(D_BACKEND, "BACKEND: %s.%s.%s: no values stored in database for range %lu to %lu",
host->hostname, st->id, rd->id,
(unsigned long)after, (unsigned long)before
);
return NAN;
}
if(unlikely((options & BACKEND_SOURCE_BITS) == BACKEND_SOURCE_DATA_SUM))
return sum;
return sum / (calculated_number)counter;
}
RRDR *rrd2rrdr(
RRDSET *st
, long points_requested
, long long after_requested
, long long before_requested
, RRDR_GROUPING group_method
, long group_time_requested
, RRDR_OPTIONS options
, const char *dimensions
) {
int aligned = !(options & RRDR_OPTION_NOT_ALIGNED);
int absolute_period_requested = -1;
time_t first_entry_t = rrdset_first_entry_t(st);
time_t last_entry_t = rrdset_last_entry_t(st);
if(before_requested == 0 && after_requested == 0) {
// dump the all the data
before_requested = last_entry_t;
after_requested = first_entry_t;
absolute_period_requested = 0;
}
// allow relative for before (smaller than API_RELATIVE_TIME_MAX)
if(((before_requested < 0)?-before_requested:before_requested) <= API_RELATIVE_TIME_MAX) {
if(abs(before_requested) % st->update_every) {
// make sure it is multiple of st->update_every
if(before_requested < 0) before_requested = before_requested - st->update_every - before_requested % st->update_every;
else before_requested = before_requested + st->update_every - before_requested % st->update_every;
}
if(before_requested > 0) before_requested = first_entry_t + before_requested;
else before_requested = last_entry_t + before_requested;
absolute_period_requested = 0;
}
// allow relative for after (smaller than API_RELATIVE_TIME_MAX)
if(((after_requested < 0)?-after_requested:after_requested) <= API_RELATIVE_TIME_MAX) {
if(after_requested == 0) after_requested = -st->update_every;
if(abs(after_requested) % st->update_every) {
// make sure it is multiple of st->update_every
if(after_requested < 0) after_requested = after_requested - st->update_every - after_requested % st->update_every;
else after_requested = after_requested + st->update_every - after_requested % st->update_every;
}
after_requested = before_requested + after_requested;
absolute_period_requested = 0;
}
if(absolute_period_requested == -1)
absolute_period_requested = 1;
// make sure they are within our timeframe
if(before_requested > last_entry_t) before_requested = last_entry_t;
if(before_requested < first_entry_t) before_requested = first_entry_t;
if(after_requested > last_entry_t) after_requested = last_entry_t;
if(after_requested < first_entry_t) after_requested = first_entry_t;
// check if they are reversed
if(after_requested > before_requested) {
time_t tmp = before_requested;
before_requested = after_requested;
after_requested = tmp;
}
// the duration of the chart
time_t duration = before_requested - after_requested;
long available_points = duration / st->update_every;
if(duration <= 0 || available_points <= 0)
return rrdr_create(st, 1);
// check the number of wanted points in the result
if(unlikely(points_requested < 0)) points_requested = -points_requested;
if(unlikely(points_requested > available_points)) points_requested = available_points;
if(unlikely(points_requested == 0)) points_requested = available_points;
// calculate the desired grouping of source data points
long group = available_points / points_requested;
if(unlikely(group <= 0)) group = 1;
if(unlikely(available_points % points_requested > points_requested / 2)) group++; // rounding to the closest integer
// group_time enforces a certain grouping multiple
calculated_number group_sum_divisor = 1.0;
long group_points = 1;
if(unlikely(group_time_requested > st->update_every)) {
if (unlikely(group_time_requested > duration)) {
// group_time is above the available duration
#ifdef NETDATA_INTERNAL_CHECKS
info("INTERNAL CHECK: %s: requested gtime %ld secs, is greater than the desired duration %ld secs", st->id, group_time_requested, duration);
#endif
group = available_points; // use all the points
}
else {
// the points we should group to satisfy gtime
group_points = group_time_requested / st->update_every;
if(unlikely(group_time_requested % group_points)) {
#ifdef NETDATA_INTERNAL_CHECKS
info("INTERNAL CHECK: %s: requested gtime %ld secs, is not a multiple of the chart's data collection frequency %d secs", st->id, group_time_requested, st->update_every);
#endif
group_points++;
}
// adapt group according to group_points
if(unlikely(group < group_points)) group = group_points; // do not allow grouping below the desired one
if(unlikely(group % group_points)) group += group_points - (group % group_points); // make sure group is multiple of group_points
//group_sum_divisor = group / group_points;
group_sum_divisor = (calculated_number)(group * st->update_every) / (calculated_number)group_time_requested;
}
}
// now that we have group,
// align the requested timeframe to fit it.
if(aligned) {
// alignement has been requested, so align the values
before_requested -= (before_requested % group);
after_requested -= (after_requested % group);
}
// we align the request on requested_before
time_t before_wanted = before_requested;
if(likely(before_wanted > last_entry_t)) {
#ifdef NETDATA_INTERNAL_CHECKS
error("INTERNAL ERROR: rrd2rrdr() on %s, before_wanted is after db max", st->name);
#endif
before_wanted = last_entry_t - (last_entry_t % ( ((aligned)?group:1) * st->update_every ));
}
size_t before_slot = rrdset_time2slot(st, before_wanted);
// we need to estimate the number of points, for having
// an integer number of values per point
long points_wanted = (before_wanted - after_requested) / st->update_every / group;
time_t after_wanted = before_wanted - (points_wanted * group * st->update_every) + st->update_every;
if(unlikely(after_wanted < first_entry_t)) {
// hm... we go to the past, calculate again points_wanted using all the db from before_wanted to the beginning
points_wanted = (before_wanted - first_entry_t) / group;
// recalculate after wanted with the new number of points
after_wanted = before_wanted - (points_wanted * group * st->update_every) + st->update_every;
if(unlikely(after_wanted < first_entry_t)) {
#ifdef NETDATA_INTERNAL_CHECKS
error("INTERNAL ERROR: rrd2rrdr() on %s, after_wanted is before db min", st->name);
#endif
after_wanted = first_entry_t - (first_entry_t % ( ((aligned)?group:1) * st->update_every )) + ( ((aligned)?group:1) * st->update_every );
}
}
size_t after_slot = rrdset_time2slot(st, after_wanted);
// check if they are reversed
if(unlikely(after_wanted > before_wanted)) {
#ifdef NETDATA_INTERNAL_CHECKS
error("INTERNAL ERROR: rrd2rrdr() on %s, reversed wanted after/before", st->name);
#endif
time_t tmp = before_wanted;
before_wanted = after_wanted;
after_wanted = tmp;
}
// recalculate points_wanted using the final time-frame
points_wanted = (before_wanted - after_wanted) / st->update_every / group + 1;
if(unlikely(points_wanted < 0)) {
#ifdef NETDATA_INTERNAL_CHECKS
error("INTERNAL ERROR: rrd2rrdr() on %s, points_wanted is %ld", st->name, points_wanted);
#endif
points_wanted = 0;
}
#ifdef NETDATA_INTERNAL_CHECKS
duration = before_wanted - after_wanted;
if(after_wanted < first_entry_t)
error("INTERNAL CHECK: after_wanted %u is too small, minimum %u", (uint32_t)after_wanted, (uint32_t)first_entry_t);
if(after_wanted > last_entry_t)
error("INTERNAL CHECK: after_wanted %u is too big, maximum %u", (uint32_t)after_wanted, (uint32_t)last_entry_t);
if(before_wanted < first_entry_t)
error("INTERNAL CHECK: before_wanted %u is too small, minimum %u", (uint32_t)before_wanted, (uint32_t)first_entry_t);
if(before_wanted > last_entry_t)
error("INTERNAL CHECK: before_wanted %u is too big, maximum %u", (uint32_t)before_wanted, (uint32_t)last_entry_t);
if(before_slot >= (size_t)st->entries)
error("INTERNAL CHECK: before_slot is invalid %zu, expected 0 to %ld", before_slot, st->entries - 1);
if(after_slot >= (size_t)st->entries)
error("INTERNAL CHECK: after_slot is invalid %zu, expected 0 to %ld", after_slot, st->entries - 1);
if(points_wanted > (before_wanted - after_wanted) / group / st->update_every + 1)
error("INTERNAL CHECK: points_wanted %ld is more than points %ld", points_wanted, (before_wanted - after_wanted) / group / st->update_every + 1);
if(group < group_points)
error("INTERNAL CHECK: group %ld is less than the desired group points %ld", group, group_points);
if(group > group_points && group % group_points)
error("INTERNAL CHECK: group %ld is not a multiple of the desired group points %ld", group, group_points);
#endif
// -------------------------------------------------------------------------
// initialize our result set
// this also locks the chart for us
RRDR *r = rrdr_create(st, points_wanted);
if(unlikely(!r)) {
#ifdef NETDATA_INTERNAL_CHECKS
error("INTERNAL CHECK: Cannot create RRDR for %s, after=%u, before=%u, duration=%u, points=%ld", st->id, (uint32_t)after_wanted, (uint32_t)before_wanted, (uint32_t)duration, points_wanted);
#endif
return NULL;
}
if(unlikely(!r->d || !points_wanted)) {
#ifdef NETDATA_INTERNAL_CHECKS
error("INTERNAL CHECK: Returning empty RRDR (no dimensions in RRDSET) for %s, after=%u, before=%u, duration=%zu, points=%ld", st->id, (uint32_t)after_wanted, (uint32_t)before_wanted, (size_t)duration, points_wanted);
#endif
return r;
}
if(unlikely(absolute_period_requested == 1))
r->result_options |= RRDR_RESULT_OPTION_ABSOLUTE;
else
r->result_options |= RRDR_RESULT_OPTION_RELATIVE;
// find how many dimensions we have
long dimensions_count = r->d;
// -------------------------------------------------------------------------
// initialize RRDR
r->group = group;
r->update_every = (int)group * st->update_every;
r->before = before_wanted;
r->after = after_wanted;
r->group_points = group_points;
r->group_sum_divisor = group_sum_divisor;
// -------------------------------------------------------------------------
// assign the processor functions
{
int i, found = 0;
for(i = 0; !found && api_v1_data_groups[i].name ;i++) {
if(api_v1_data_groups[i].value == group_method) {
r->grouping_init = api_v1_data_groups[i].init;
r->grouping_reset = api_v1_data_groups[i].reset;
r->grouping_free = api_v1_data_groups[i].free;
r->grouping_add = api_v1_data_groups[i].add;
r->grouping_flush = api_v1_data_groups[i].flush;
found = 1;
}
}
if(!found) {
errno = 0;
#ifdef NETDATA_INTERNAL_CHECKS
error("INTERNAL ERROR: grouping method %u not found for chart '%s'. Using 'average'", (unsigned int)group_method, r->st->name);
#endif
r->grouping_init = grouping_init_average;
r->grouping_reset = grouping_reset_average;
r->grouping_free = grouping_free_average;
r->grouping_add = grouping_add_average;
r->grouping_flush = grouping_flush_average;
}
}
// allocate any memory required by the grouping method
r->grouping_data = r->grouping_init(r);
// -------------------------------------------------------------------------
// disable the not-wanted dimensions
rrdset_check_rdlock(st);
if(dimensions)
rrdr_disable_not_selected_dimensions(r, options, dimensions);
// -------------------------------------------------------------------------
// do the work for each dimension
time_t max_after = 0, min_before = 0;
long max_rows = 0;
RRDDIM *rd;
long c, dimensions_used = 0, dimensions_nonzero = 0;
for(rd = st->dimensions, c = 0 ; rd && c < dimensions_count ; rd = rd->next, c++) {
// if we need a percentage, we need to calculate all dimensions
if(unlikely(!(options & RRDR_OPTION_PERCENTAGE) && (r->od[c] & RRDR_DIMENSION_HIDDEN)))
continue;
// reset the grouping for the new dimension
r->grouping_reset(r);
do_dimension(
r
, points_wanted
, rd
, c
, after_slot
, before_slot
, after_wanted
, before_wanted
);
if(r->od[c] & RRDR_DIMENSION_NONZERO)
dimensions_nonzero++;
// verify all dimensions are aligned
if(unlikely(!dimensions_used)) {
min_before = r->before;
max_after = r->after;
max_rows = r->rows;
}
else {
if(r->after != max_after) {
#ifdef NETDATA_INTERNAL_CHECKS
error("INTERNAL ERROR: 'after' mismatch between dimensions for chart '%s': max is %zu, dimension '%s' has %zu",
st->name, (size_t)max_after, rd->name, (size_t)r->after);
#endif
r->after = (r->after > max_after) ? r->after : max_after;
}
if(r->before != min_before) {
#ifdef NETDATA_INTERNAL_CHECKS
error("INTERNAL ERROR: 'before' mismatch between dimensions for chart '%s': max is %zu, dimension '%s' has %zu",
st->name, (size_t)min_before, rd->name, (size_t)r->before);
#endif
r->before = (r->before < min_before) ? r->before : min_before;
}
if(r->rows != max_rows) {
#ifdef NETDATA_INTERNAL_CHECKS
error("INTERNAL ERROR: 'rows' mismatch between dimensions for chart '%s': max is %zu, dimension '%s' has %zu",
st->name, (size_t)max_rows, rd->name, (size_t)r->rows);
#endif
r->rows = (r->rows > max_rows) ? r->rows : max_rows;
}
}
dimensions_used++;
}
#ifdef NETDATA_INTERNAL_CHECKS
if(r->log)
rrd2rrdr_log_request_response_metdata(r, group_method, aligned, group, group_time_requested, group_points, after_wanted, after_requested, before_wanted, before_requested, points_requested, points_wanted, after_slot, before_slot, r->log);
if(r->rows != points_wanted)
rrd2rrdr_log_request_response_metdata(r, group_method, aligned, group, group_time_requested, group_points, after_wanted, after_requested, before_wanted, before_requested, points_requested, points_wanted, after_slot, before_slot, "got 'points' is not wanted 'points'");
if(aligned && (r->before % group) != 0)
rrd2rrdr_log_request_response_metdata(r, group_method, aligned, group, group_time_requested, group_points, after_wanted, after_requested, before_wanted, before_requested, points_requested, points_wanted, after_slot, before_slot, "'before' is not aligned but alignment is required");
// 'after' should not be aligned, since we start inside the first group
//if(aligned && (r->after % group) != 0)
// rrd2rrdr_log_request_response_metdata(r, group_method, aligned, group, group_time_requested, group_points, after_wanted, after_requested, before_wanted, before_requested, points_requested, points_wanted, after_slot, before_slot, "'after' is not aligned but alignment is required");
if(r->before != before_requested)
rrd2rrdr_log_request_response_metdata(r, group_method, aligned, group, group_time_requested, group_points, after_wanted, after_requested, before_wanted, before_requested, points_requested, points_wanted, after_slot, before_slot, "chart is not aligned to requested 'before'");
if(r->before != before_wanted)
rrd2rrdr_log_request_response_metdata(r, group_method, aligned, group, group_time_requested, group_points, after_wanted, after_requested, before_wanted, before_requested, points_requested, points_wanted, after_slot, before_slot, "got 'before' is not wanted 'before'");
// reported 'after' varies, depending on group
if((r->after - (group - 1) * r->st->update_every) != after_wanted)
rrd2rrdr_log_request_response_metdata(r, group_method, aligned, group, group_time_requested, group_points, after_wanted, after_requested, before_wanted, before_requested, points_requested, points_wanted, after_slot, before_slot, "got 'after' is not wanted 'after'");
#endif
// free all resources used by the grouping method
r->grouping_free(r);
// when all the dimensions are zero, we should return all of them
if(unlikely(options & RRDR_OPTION_NONZERO && !dimensions_nonzero)) {
// all the dimensions are zero
// mark them as NONZERO to send them all
for(rd = st->dimensions, c = 0 ; rd && c < dimensions_count ; rd = rd->next, c++) {
if(unlikely(r->od[c] & RRDR_DIMENSION_HIDDEN)) continue;
r->od[c] |= RRDR_DIMENSION_NONZERO;
}
}
return r;
}
