intermediate changes

ref:cde9a383711a11544ce7e107a78147fb96cc4029

1 files changed, 84 insertions, 0 deletions

diff --git a/library/cpp/lwtrace/perf.cpp b/library/cpp/lwtrace/perf.cpp
new file mode 100644
index 0000000000..03b68586ea
--- /dev/null
+++ b/library/cpp/lwtrace/perf.cpp
@@ -0,0 +1,84 @@
+#include "perf.h"
+
+#include "probes.h"
+
+#include <util/system/datetime.h>
+#include <util/system/hp_timer.h>
+
+namespace NLWTrace {
+    LWTRACE_USING(LWTRACE_INTERNAL_PROVIDER);
+
+    TCpuTracker::TCpuTracker()
+        : MinReportPeriod(NHPTimer::GetCyclesPerSecond())
+    {
+        ResetStats();
+    }
+
+    void TCpuTracker::Enter() {
+        LastTs = GetCycleCount();
+    }
+
+    void TCpuTracker::Exit(const TProbe* probe) {
+        ui64 exitTs = GetCycleCount();
+        if (exitTs < LastTs) {
+            return; // probably TSC was reset
+        }
+        ui64 cycles = exitTs - LastTs;
+        LastTs = exitTs;
+
+        AddStats(probe, cycles);
+    }
+
+    void TCpuTracker::AddStats(const TProbe* probe, ui64 cycles) {
+        if (MaxCycles < cycles) {
+            MaxProbe = probe;
+            MaxCycles = cycles;
+        }
+        if (MinCycles > cycles) {
+            MinCycles = cycles;
+        }
+        ProbeCycles += cycles;
+        Count++;
+
+        if (LastTs - LastReportTs > MinReportPeriod) {
+            Report();
+        }
+    }
+
+    void TCpuTracker::ResetStats() {
+        MaxCycles = 0;
+        MaxProbe = nullptr;
+        MinCycles = ui64(-1);
+        ProbeCycles = 0;
+        Count = 0;
+    }
+
+    void TCpuTracker::Report() {
+        if (!Reporting) {
+            Reporting = true;
+            ReportNotReentrant();
+            Reporting = false;
+        }
+    }
+
+    void TCpuTracker::ReportNotReentrant() {
+        if (LastReportTs && Count > 0 && LastTs > LastReportTs) {
+            ui64 reportPeriod = LastTs - LastReportTs;
+            double share = double(ProbeCycles) / reportPeriod;
+            double minMs = MilliSeconds(MinCycles);
+            double maxMs = MilliSeconds(MaxCycles);
+            double avgMs = MilliSeconds(ProbeCycles) / Count;
+            LastReportTs = LastTs;
+            ResetStats();
+            LWPROBE(PerfReport, share, minMs, maxMs, avgMs);
+        } else {
+            LastReportTs = LastTs;
+            ResetStats();
+        }
+    }
+
+    double TCpuTracker::MilliSeconds(ui64 cycles) {
+        return NHPTimer::GetSeconds(cycles) * 1000.0;
+    }
+
+}