#include "metrics.h"
#include <assert.h>
+#include <math.h>
+#include <algorithm>
+#include <chrono>
#include <locale>
#include <sstream>
using namespace std;
+using namespace std::chrono;
Metrics global_metrics;
+double get_timestamp_for_metrics()
+{
+ return duration<double>(system_clock::now().time_since_epoch()).count();
+}
+
+string Metrics::serialize_name(const string &name, const vector<pair<string, string>> &labels)
+{
+ return "nageru_" + name + serialize_labels(labels);
+}
+
+string Metrics::serialize_labels(const vector<pair<string, string>> &labels)
+{
+ if (labels.empty()) {
+ return "";
+ }
+
+ string label_str;
+ for (const pair<string, string> &label : labels) {
+ if (!label_str.empty()) {
+ label_str += ",";
+ }
+ label_str += label.first + "=\"" + label.second + "\"";
+ }
+ return "{" + label_str + "}";
+}
+
void Metrics::add(const string &name, const vector<pair<string, string>> &labels, atomic<int64_t> *location, Metrics::Type type)
{
Metric metric;
metric.data_type = DATA_TYPE_INT64;
- metric.name = name;
- metric.labels = labels;
metric.location_int64 = location;
lock_guard<mutex> lock(mu);
- metrics.push_back(metric);
+ metrics.emplace(MetricKey(name, labels), metric);
assert(types.count(name) == 0 || types[name] == type);
types[name] = type;
}
{
Metric metric;
metric.data_type = DATA_TYPE_DOUBLE;
- metric.name = name;
- metric.labels = labels;
metric.location_double = location;
lock_guard<mutex> lock(mu);
- metrics.push_back(metric);
+ metrics.emplace(MetricKey(name, labels), metric);
assert(types.count(name) == 0 || types[name] == type);
types[name] = type;
}
+void Metrics::add(const string &name, const vector<pair<string, string>> &labels, Histogram *location, Laziness laziness)
+{
+ Metric metric;
+ metric.data_type = DATA_TYPE_HISTOGRAM;
+ metric.laziness = laziness;
+ metric.location_histogram = location;
+
+ lock_guard<mutex> lock(mu);
+ metrics.emplace(MetricKey(name, labels), metric);
+ assert(types.count(name) == 0 || types[name] == TYPE_HISTOGRAM);
+ types[name] = TYPE_HISTOGRAM;
+}
+
+void Metrics::remove(const string &name, const vector<pair<string, string>> &labels)
+{
+ lock_guard<mutex> lock(mu);
+
+ auto it = metrics.find(MetricKey(name, labels));
+ assert(it != metrics.end());
+
+ // If this is the last metric with this name, remove the type as well.
+ if (!((it != metrics.begin() && prev(it)->first.name == name) ||
+ (it != metrics.end() && next(it)->first.name == name))) {
+ types.erase(name);
+ }
+
+ metrics.erase(it);
+}
+
string Metrics::serialize() const
{
stringstream ss;
ss.precision(20);
lock_guard<mutex> lock(mu);
- for (const auto &name_and_type : types) {
- if (name_and_type.second == TYPE_GAUGE) {
- ss << "# TYPE nageru_" << name_and_type.first << " gauge\n";
- }
- }
- for (const Metric &metric : metrics) {
- string name;
- if (metric.labels.empty()) {
- name = "nageru_" + metric.name;
- } else {
- name = "nageru_" + metric.name + "{";
- bool first = true;
- for (const pair<string, string> &label : metric.labels) {
- if (!first) {
- name += ",";
- }
- first = false;
- name += label.first + "=\"" + label.second + "\"";
+ auto type_it = types.cbegin();
+ for (const auto &key_and_metric : metrics) {
+ string name = "nageru_" + key_and_metric.first.name + key_and_metric.first.serialized_labels;
+ const Metric &metric = key_and_metric.second;
+
+ if (type_it != types.cend() &&
+ key_and_metric.first.name == type_it->first) {
+ // It's the first time we print out any metric with this name,
+ // so add the type header.
+ if (type_it->second == TYPE_GAUGE) {
+ ss << "# TYPE nageru_" << type_it->first << " gauge\n";
+ } else if (type_it->second == TYPE_HISTOGRAM) {
+ ss << "# TYPE nageru_" << type_it->first << " histogram\n";
}
- name += "}";
+ ++type_it;
}
if (metric.data_type == DATA_TYPE_INT64) {
- ss << "nageru_" << name << " " << metric.location_int64->load() << "\n";
+ ss << name << " " << metric.location_int64->load() << "\n";
+ } else if (metric.data_type == DATA_TYPE_DOUBLE) {
+ double val = metric.location_double->load();
+ if (isnan(val)) {
+ // Prometheus can't handle “-nan”.
+ ss << name << " NaN\n";
+ } else {
+ ss << name << " " << val << "\n";
+ }
} else {
- ss << "nageru_" << name << " " << metric.location_double->load() << "\n";
+ ss << metric.location_histogram->serialize(metric.laziness, key_and_metric.first.name, key_and_metric.first.labels);
+ }
+ }
+
+ return ss.str();
+}
+
+void Histogram::init(const vector<double> &bucket_vals)
+{
+ this->num_buckets = bucket_vals.size();
+ buckets.reset(new Bucket[num_buckets]);
+ for (size_t i = 0; i < num_buckets; ++i) {
+ buckets[i].val = bucket_vals[i];
+ }
+}
+
+void Histogram::init_uniform(size_t num_buckets)
+{
+ this->num_buckets = num_buckets;
+ buckets.reset(new Bucket[num_buckets]);
+ for (size_t i = 0; i < num_buckets; ++i) {
+ buckets[i].val = i;
+ }
+}
+
+void Histogram::init_geometric(double min, double max, size_t num_buckets)
+{
+ this->num_buckets = num_buckets;
+ buckets.reset(new Bucket[num_buckets]);
+ for (size_t i = 0; i < num_buckets; ++i) {
+ buckets[i].val = min * pow(max / min, double(i) / (num_buckets - 1));
+ }
+}
+
+void Histogram::count_event(double val)
+{
+ Bucket ref_bucket;
+ ref_bucket.val = val;
+ auto it = lower_bound(buckets.get(), buckets.get() + num_buckets, ref_bucket,
+ [](const Bucket &a, const Bucket &b) { return a.val < b.val; });
+ if (it == buckets.get() + num_buckets) {
+ ++count_after_last_bucket;
+ } else {
+ ++it->count;
+ }
+ // Non-atomic add, but that's fine, since there are no concurrent writers.
+ sum = sum + val;
+}
+
+string Histogram::serialize(Metrics::Laziness laziness, const string &name, const vector<pair<string, string>> &labels) const
+{
+ // Check if the histogram is empty and should not be serialized.
+ if (laziness == Metrics::PRINT_WHEN_NONEMPTY && count_after_last_bucket.load() == 0) {
+ bool empty = true;
+ for (size_t bucket_idx = 0; bucket_idx < num_buckets; ++bucket_idx) {
+ if (buckets[bucket_idx].count.load() != 0) {
+ empty = false;
+ break;
+ }
}
+ if (empty) {
+ return "";
+ }
+ }
+
+ stringstream ss;
+ ss.imbue(locale("C"));
+ ss.precision(20);
+
+ int64_t count = 0;
+ for (size_t bucket_idx = 0; bucket_idx < num_buckets; ++bucket_idx) {
+ stringstream le_ss;
+ le_ss.imbue(locale("C"));
+ le_ss.precision(20);
+ le_ss << buckets[bucket_idx].val;
+ vector<pair<string, string>> bucket_labels = labels;
+ bucket_labels.emplace_back("le", le_ss.str());
+
+ count += buckets[bucket_idx].count.load();
+ ss << Metrics::serialize_name(name + "_bucket", bucket_labels) << " " << count << "\n";
}
+ count += count_after_last_bucket.load();
+
+ ss << Metrics::serialize_name(name + "_sum", labels) << " " << sum.load() << "\n";
+ ss << Metrics::serialize_name(name + "_count", labels) << " " << count << "\n";
+
return ss.str();
}
projects / nageru / blobdiff