summaryrefslogtreecommitdiffstats
path: root/web/api/queries/percentile/percentile.c
diff options
context:
space:
mode:
Diffstat (limited to 'web/api/queries/percentile/percentile.c')
-rw-r--r--web/api/queries/percentile/percentile.c169
1 files changed, 169 insertions, 0 deletions
diff --git a/web/api/queries/percentile/percentile.c b/web/api/queries/percentile/percentile.c
new file mode 100644
index 00000000..88f8600d
--- /dev/null
+++ b/web/api/queries/percentile/percentile.c
@@ -0,0 +1,169 @@
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+#include "percentile.h"
+
+// ----------------------------------------------------------------------------
+// median
+
+struct grouping_percentile {
+ size_t series_size;
+ size_t next_pos;
+ NETDATA_DOUBLE percent;
+
+ NETDATA_DOUBLE *series;
+};
+
+static void grouping_create_percentile_internal(RRDR *r, const char *options, NETDATA_DOUBLE def) {
+ long entries = r->group;
+ if(entries < 10) entries = 10;
+
+ struct grouping_percentile *g = (struct grouping_percentile *)onewayalloc_callocz(r->internal.owa, 1, sizeof(struct grouping_percentile));
+ g->series = onewayalloc_mallocz(r->internal.owa, entries * sizeof(NETDATA_DOUBLE));
+ g->series_size = (size_t)entries;
+
+ g->percent = def;
+ if(options && *options) {
+ g->percent = str2ndd(options, NULL);
+ if(!netdata_double_isnumber(g->percent)) g->percent = 0.0;
+ if(g->percent < 0.0) g->percent = 0.0;
+ if(g->percent > 100.0) g->percent = 100.0;
+ }
+
+ g->percent = g->percent / 100.0;
+ r->internal.grouping_data = g;
+}
+
+void grouping_create_percentile25(RRDR *r, const char *options) {
+ grouping_create_percentile_internal(r, options, 25.0);
+}
+void grouping_create_percentile50(RRDR *r, const char *options) {
+ grouping_create_percentile_internal(r, options, 50.0);
+}
+void grouping_create_percentile75(RRDR *r, const char *options) {
+ grouping_create_percentile_internal(r, options, 75.0);
+}
+void grouping_create_percentile80(RRDR *r, const char *options) {
+ grouping_create_percentile_internal(r, options, 80.0);
+}
+void grouping_create_percentile90(RRDR *r, const char *options) {
+ grouping_create_percentile_internal(r, options, 90.0);
+}
+void grouping_create_percentile95(RRDR *r, const char *options) {
+ grouping_create_percentile_internal(r, options, 95.0);
+}
+void grouping_create_percentile97(RRDR *r, const char *options) {
+ grouping_create_percentile_internal(r, options, 97.0);
+}
+void grouping_create_percentile98(RRDR *r, const char *options) {
+ grouping_create_percentile_internal(r, options, 98.0);
+}
+void grouping_create_percentile99(RRDR *r, const char *options) {
+ grouping_create_percentile_internal(r, options, 99.0);
+}
+
+// resets when switches dimensions
+// so, clear everything to restart
+void grouping_reset_percentile(RRDR *r) {
+ struct grouping_percentile *g = (struct grouping_percentile *)r->internal.grouping_data;
+ g->next_pos = 0;
+}
+
+void grouping_free_percentile(RRDR *r) {
+ struct grouping_percentile *g = (struct grouping_percentile *)r->internal.grouping_data;
+ if(g) onewayalloc_freez(r->internal.owa, g->series);
+
+ onewayalloc_freez(r->internal.owa, r->internal.grouping_data);
+ r->internal.grouping_data = NULL;
+}
+
+void grouping_add_percentile(RRDR *r, NETDATA_DOUBLE value) {
+ struct grouping_percentile *g = (struct grouping_percentile *)r->internal.grouping_data;
+
+ if(unlikely(g->next_pos >= g->series_size)) {
+ g->series = onewayalloc_doublesize( r->internal.owa, g->series, g->series_size * sizeof(NETDATA_DOUBLE));
+ g->series_size *= 2;
+ }
+
+ g->series[g->next_pos++] = value;
+}
+
+NETDATA_DOUBLE grouping_flush_percentile(RRDR *r, RRDR_VALUE_FLAGS *rrdr_value_options_ptr) {
+ struct grouping_percentile *g = (struct grouping_percentile *)r->internal.grouping_data;
+
+ NETDATA_DOUBLE value;
+ size_t available_slots = g->next_pos;
+
+ if(unlikely(!available_slots)) {
+ value = 0.0;
+ *rrdr_value_options_ptr |= RRDR_VALUE_EMPTY;
+ }
+ else if(available_slots == 1) {
+ value = g->series[0];
+ }
+ else {
+ sort_series(g->series, available_slots);
+
+ NETDATA_DOUBLE min = g->series[0];
+ NETDATA_DOUBLE max = g->series[available_slots - 1];
+
+ if (min != max) {
+ size_t slots_to_use = (size_t)((NETDATA_DOUBLE)available_slots * g->percent);
+ if(!slots_to_use) slots_to_use = 1;
+
+ NETDATA_DOUBLE percent_to_use = (NETDATA_DOUBLE)slots_to_use / (NETDATA_DOUBLE)available_slots;
+ NETDATA_DOUBLE percent_delta = g->percent - percent_to_use;
+
+ NETDATA_DOUBLE percent_interpolation_slot = 0.0;
+ NETDATA_DOUBLE percent_last_slot = 0.0;
+ if(percent_delta > 0.0) {
+ NETDATA_DOUBLE percent_to_use_plus_1_slot = (NETDATA_DOUBLE)(slots_to_use + 1) / (NETDATA_DOUBLE)available_slots;
+ NETDATA_DOUBLE percent_1slot = percent_to_use_plus_1_slot - percent_to_use;
+
+ percent_interpolation_slot = percent_delta / percent_1slot;
+ percent_last_slot = 1 - percent_interpolation_slot;
+ }
+
+ int start_slot, stop_slot, step, last_slot, interpolation_slot;
+ if(min >= 0.0 && max >= 0.0) {
+ start_slot = 0;
+ stop_slot = start_slot + (int)slots_to_use;
+ last_slot = stop_slot - 1;
+ interpolation_slot = stop_slot;
+ step = 1;
+ }
+ else {
+ start_slot = (int)available_slots - 1;
+ stop_slot = start_slot - (int)slots_to_use;
+ last_slot = stop_slot + 1;
+ interpolation_slot = stop_slot;
+ step = -1;
+ }
+
+ value = 0.0;
+ for(int slot = start_slot; slot != stop_slot ; slot += step)
+ value += g->series[slot];
+
+ size_t counted = slots_to_use;
+ if(percent_interpolation_slot > 0.0 && interpolation_slot >= 0 && interpolation_slot < (int)available_slots) {
+ value += g->series[interpolation_slot] * percent_interpolation_slot;
+ value += g->series[last_slot] * percent_last_slot;
+ counted++;
+ }
+
+ value = value / (NETDATA_DOUBLE)counted;
+ }
+ else
+ value = min;
+ }
+
+ if(unlikely(!netdata_double_isnumber(value))) {
+ value = 0.0;
+ *rrdr_value_options_ptr |= RRDR_VALUE_EMPTY;
+ }
+
+ //log_series_to_stderr(g->series, g->next_pos, value, "percentile");
+
+ g->next_pos = 0;
+
+ return value;
+}