1 files changed, 77 insertions, 0 deletions
diff --git a/src/rocksdb/monitoring/perf_step_timer.h b/src/rocksdb/monitoring/perf_step_timer.h
new file mode 100644
index 000000000..8deb31252
--- /dev/null
+++ b/src/rocksdb/monitoring/perf_step_timer.h
@@ -0,0 +1,77 @@
+//  Copyright (c) 2011-present, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under both the GPLv2 (found in the
+//  COPYING file in the root directory) and Apache 2.0 License
+//  (found in the LICENSE.Apache file in the root directory).
+//
+#pragma once
+#include "monitoring/perf_level_imp.h"
+#include "monitoring/statistics.h"
+#include "rocksdb/system_clock.h"
+
+namespace ROCKSDB_NAMESPACE {
+
+class PerfStepTimer {
+ public:
+  explicit PerfStepTimer(
+      uint64_t* metric, SystemClock* clock = nullptr, bool use_cpu_time = false,
+      PerfLevel enable_level = PerfLevel::kEnableTimeExceptForMutex,
+      Statistics* statistics = nullptr, uint32_t ticker_type = 0)
+      : perf_counter_enabled_(perf_level >= enable_level),
+        use_cpu_time_(use_cpu_time),
+        ticker_type_(ticker_type),
+        clock_((perf_counter_enabled_ || statistics != nullptr)
+                   ? (clock ? clock : SystemClock::Default().get())
+                   : nullptr),
+        start_(0),
+        metric_(metric),
+        statistics_(statistics) {}
+
+  ~PerfStepTimer() { Stop(); }
+
+  void Start() {
+    if (perf_counter_enabled_ || statistics_ != nullptr) {
+      start_ = time_now();
+    }
+  }
+
+  void Measure() {
+    if (start_) {
+      uint64_t now = time_now();
+      *metric_ += now - start_;
+      start_ = now;
+    }
+  }
+
+  void Stop() {
+    if (start_) {
+      uint64_t duration = time_now() - start_;
+      if (perf_counter_enabled_) {
+        *metric_ += duration;
+      }
+
+      if (statistics_ != nullptr) {
+        RecordTick(statistics_, ticker_type_, duration);
+      }
+      start_ = 0;
+    }
+  }
+
+ private:
+  uint64_t time_now() {
+    if (!use_cpu_time_) {
+      return clock_->NowNanos();
+    } else {
+      return clock_->CPUNanos();
+    }
+  }
+
+  const bool perf_counter_enabled_;
+  const bool use_cpu_time_;
+  uint32_t ticker_type_;
+  SystemClock* const clock_;
+  uint64_t start_;
+  uint64_t* metric_;
+  Statistics* statistics_;
+};
+
+}  // namespace ROCKSDB_NAMESPACE