diff --git a/include/ylt/metric/summary.hpp b/include/ylt/metric/summary.hpp index 7d36c86ec..5a565a8ed 100644 --- a/include/ylt/metric/summary.hpp +++ b/include/ylt/metric/summary.hpp @@ -37,7 +37,7 @@ YLT_REFL(json_summary_t, name, help, type, labels_name, quantiles_key, metrics); class summary_t : public static_metric { public: summary_t(std::string name, std::string help, std::vector quantiles, - std::chrono::seconds max_age = std::chrono::seconds{60}) + std::chrono::seconds max_age = std::chrono::seconds{0}) : static_metric(MetricType::Summary, std::move(name), std::move(help)), quantiles_(std::move(quantiles)), impl_(quantiles_, @@ -133,14 +133,16 @@ class summary_t : public static_metric { private: std::vector quantiles_; - ylt::metric::detail::summary_impl<> impl_; + ylt::metric::detail::summary_impl impl_; }; template class basic_dynamic_summary - : public dynamic_metric_impl, N> { + : public dynamic_metric_impl, + N> { private: - using Base = dynamic_metric_impl, N>; + using Base = + dynamic_metric_impl, N>; public: basic_dynamic_summary( diff --git a/include/ylt/metric/summary_impl.hpp b/include/ylt/metric/summary_impl.hpp index cf48ed36b..ce853af64 100644 --- a/include/ylt/metric/summary_impl.hpp +++ b/include/ylt/metric/summary_impl.hpp @@ -7,12 +7,15 @@ #include #include #include +#include #include namespace ylt::metric::detail { -template +template class summary_impl { + static_assert(sizeof(uint_type) >= 4); + static_assert(std::is_unsigned_v); constexpr static uint32_t decode_impl(uint16_t float16_value) { float16_value <<= (8 - frac_bit); uint32_t sign = float16_value >> 15; @@ -57,7 +60,8 @@ class summary_impl { static constexpr float float16_max = (1ull << 63) * 2.0f; // 2^64 static uint16_t encode(float flt) { - unsigned int& fltInt32 = *(unsigned int*)&flt; + static_assert(sizeof(float) == 4); + uint32_t& fltInt32 = *(uint32_t*)&flt; if (std::abs(flt) >= float16_max || std::isnan(flt)) { flt = (fltInt32 & 0x8000'0000) ? (-float16_max) : (float16_max); } @@ -88,9 +92,9 @@ class summary_impl { struct data_t { static constexpr size_t piece_size = bucket_size / piece_cnt; - using piece_t = std::array, piece_size>; + using piece_t = std::array, piece_size>; - std::atomic& operator[](std::size_t index) { + std::atomic& operator[](std::size_t index) { piece_t* piece = arr[index / piece_size]; if (piece == nullptr) { auto ptr = new piece_t{}; @@ -122,7 +126,7 @@ class summary_impl { } template void stat_impl(uint64_t& count, - std::vector>& result, int i) { + std::vector>& result, int i) { auto piece = arr[i].load(std::memory_order_relaxed); if (piece) { if constexpr (inc_order) { @@ -146,7 +150,7 @@ class summary_impl { } } void stat(uint64_t& count, - std::vector>& result) { + std::vector>& result) { for (int i = piece_cnt - 1; i >= piece_cnt / 2; --i) { stat_impl(count, result, i); } @@ -182,36 +186,38 @@ class summary_impl { static inline const unsigned long ms_count = std::chrono::steady_clock::duration{std::chrono::milliseconds{1}}.count(); - constexpr static unsigned int near_uint32_max = 4290000000U; + constexpr static uint32_t near_uint32_max = 4290000000U; void increase(data_t& arr, uint16_t pos) { - if (arr[pos].fetch_add(1, std::memory_order::relaxed) > - near_uint32_max) /*no overflow*/ [[likely]] { - arr[pos].fetch_sub(1, std::memory_order::relaxed); - int upper = (pos < bucket_size / 2) ? (bucket_size / 2) : (bucket_size); - int lower = (pos < bucket_size / 2) ? (0) : (bucket_size / 2); - for (int delta = 1, lim = (std::max)(upper - pos, pos - lower + 1); - delta < lim; ++delta) { - if (pos + delta < upper) { - if (arr[pos + delta].fetch_add(1, std::memory_order::relaxed) <= - near_uint32_max) { - break; + auto res = arr[pos].fetch_add(1, std::memory_order::relaxed); + if constexpr (std::is_same_v) { + if (res > near_uint32_max) /*no overflow*/ [[likely]] { + arr[pos].fetch_sub(1, std::memory_order::relaxed); + int upper = (pos < bucket_size / 2) ? (bucket_size / 2) : (bucket_size); + int lower = (pos < bucket_size / 2) ? (0) : (bucket_size / 2); + for (int delta = 1, lim = (std::max)(upper - pos, pos - lower + 1); + delta < lim; ++delta) { + if (pos + delta < upper) { + if (arr[pos + delta].fetch_add(1, std::memory_order::relaxed) <= + near_uint32_max) { + break; + } + arr[pos + delta].fetch_sub(1, std::memory_order::relaxed); } - arr[pos + delta].fetch_sub(1, std::memory_order::relaxed); - } - if (pos - delta >= lower) { - if (arr[pos - delta].fetch_add(1, std::memory_order::relaxed) <= - near_uint32_max) { - break; + if (pos - delta >= lower) { + if (arr[pos - delta].fetch_add(1, std::memory_order::relaxed) <= + near_uint32_max) { + break; + } + arr[pos - delta].fetch_sub(1, std::memory_order::relaxed); } - arr[pos - delta].fetch_sub(1, std::memory_order::relaxed); } } } } struct data_copy_t { - std::vector> arr[2]; + std::vector> arr[2]; int index[2] = {}, smaller_one; void init() { if (arr[0][0] <= arr[1][0]) { @@ -231,7 +237,7 @@ class summary_impl { } } int16_t value() { return arr[smaller_one][index[smaller_one]].first; } - uint32_t count() { return arr[smaller_one][index[smaller_one]].second; } + uint_type count() { return arr[smaller_one][index[smaller_one]].second; } }; public: @@ -304,6 +310,9 @@ class summary_impl { e = 1; } auto target_count = std::min(e * count, count); + if (e == 0) { + target_count = std::min(uint64_t{1}, count); + } while (true) { if (target_count <= count_now) [[unlikely]] { result.push_back(v); diff --git a/src/metric/tests/test_metric.cpp b/src/metric/tests/test_metric.cpp index b0e2eaeb2..2bbf7553b 100644 --- a/src/metric/tests/test_metric.cpp +++ b/src/metric/tests/test_metric.cpp @@ -925,7 +925,7 @@ TEST_CASE("test summary with illegal quantities") { CHECK(str.find("test_summary_sum") != std::string::npos); CHECK(str.find("test_summary{quantile=\"") != std::string::npos); CHECK(result[0] < 0); - CHECK(result[1] < 0); + CHECK(result[1] == 0); CHECK(result[result.size() - 1] > result[result.size() - 2]); #ifdef CINATRA_ENABLE_METRIC_JSON @@ -933,7 +933,7 @@ TEST_CASE("test summary with illegal quantities") { summary.serialize_to_json(str_json); std::cout << str_json << "\n"; std::cout << str_json.size() << std::endl; - CHECK(str_json.size() == 233); + CHECK(str_json.size() == 222); #endif } @@ -969,7 +969,7 @@ TEST_CASE("test summary with many quantities") { summary.serialize_to_json(str_json); std::cout << str_json << "\n"; std::cout << str_json.size() << std::endl; - CHECK(str_json.size() == 8868); + CHECK(str_json.size() == 8857); #endif } @@ -1998,6 +1998,24 @@ TEST_CASE("test remove label value") { CHECK(!counter.has_label_value(std::vector{})); } +TEST_CASE("test static summary with 0 and 1 quantiles") { + { + ylt::metric::summary_t s("test", "help", {0, 1}); + for (uint64_t i = 0; i < 100ull; ++i) { + s.observe(1); + } + auto result = s.get_rates(); + CHECK(result[0] == 1); + CHECK(result[1] == 1); + } + { + ylt::metric::summary_t s("test", "help", {0, 1}); + auto result = s.get_rates(); + CHECK(result[0] == 0); + CHECK(result[1] == 0); + } +} + DOCTEST_MSVC_SUPPRESS_WARNING_WITH_PUSH(4007) int main(int argc, char** argv) { return doctest::Context(argc, argv).run(); } DOCTEST_MSVC_SUPPRESS_WARNING_POP \ No newline at end of file diff --git a/website/docs/zh/metric/metric_introduction.md b/website/docs/zh/metric/metric_introduction.md index 7fe11de89..a73d60a1b 100644 --- a/website/docs/zh/metric/metric_introduction.md +++ b/website/docs/zh/metric/metric_introduction.md @@ -1,6 +1,13 @@ # metric 介绍 metric 用于统计应用程序的各种指标，这些指标被用于系统见识和警报，常见的指标类型有四种：Counter、Gauge、Histogram和Summary，这些指标遵循[Prometheus](https://hulining.gitbook.io/prometheus/introduction)的数据格式。yalantinglibs提供了一系列高性能且线程安全的统计工具。 +metric 包括4种指标类型： +- couter：只会增加的指标； +- gauge：可以增加或减少的指标，它派生于counter； +- histogram：直方图，初始化的时候需要设置桶(bucket)； +- summary：分位数指标，初始化的时候需要设置桶和误差； + + ## Counter 计数器类型 Counter是一个累计类型的数据指标，它代表单调递增的计数器，其值只能在重新启动时增加或重置为 0。例如，您可以使用计数器来表示已响应的请求数，已完成或出错的任务数。 @@ -71,11 +78,7 @@ prometheus_tsdb_wal_fsync_duration_seconds_count 216 ``` # 概述 -metric 包括4种指标类型： -- couter：只会增加的指标； -- gauge：可以增加或减少的指标，它派生于counter； -- histogram：直方图，初始化的时候需要设置桶(bucket)； -- summary：分位数指标，初始化的时候需要设置桶和误差； + # label @@ -453,7 +456,11 @@ std::vector> get_bucket_counts(); // 序列化 void serialize(std::string& str); ``` -## 例子 + + +## 例子 + + ```cpp histogram_t h("test", "help", {5.0, 10.0, 20.0, 50.0, 100.0}); h.observe(23); @@ -548,7 +555,7 @@ summary每次写入的数据会被映射到一个14位的浮点数中，其指 ### 大量重复数字导致的误差 -为节省内存空间，summary内部的每个桶仅能存储一个32位数字，因此，在一个过期时间周期内同一个数字被插入超过2^32次后，为了避免溢出，新的数字会被插入到与该数字临近的桶（相差约1%）中，这可能导致一定误差。 +为节省内存空间，dynamic summary内部的每个桶仅能存储一个32位数字，因此，在一个过期时间周期内同一个数字被插入超过2^32次后，为了避免溢出，新的数字会被插入到与该数字临近的桶（相差约1%）中，这可能导致一定误差。非daynamic的summary 不会有这个问题，因为他内部使用的是64位，不可能出现溢出。 ### 过期时间误差