Accept two histograms in StopWatch

facebook · Mar 15, 2023 · 326b5b2 · 326b5b2
1 parent b0ada30
commit 326b5b2
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Showing 4 changed files with 34 additions and 28 deletions.
diff --git a/db/db_impl/db_impl_write.cc b/db/db_impl/db_impl_write.cc
@@ -1776,7 +1776,7 @@ Status DBImpl::DelayWrite(uint64_t num_bytes, WriteThread& write_thread,
   bool delayed = false;
   {
     StopWatch sw(immutable_db_options_.clock, stats_, WRITE_STALL,
-                 &time_delayed);
+                 Histograms::HISTOGRAM_ENUM_MAX, &time_delayed);
     // To avoid parallel timed delays (bad throttling), only support them
     // on the primary write queue.
     uint64_t delay;

diff --git a/db/perf_context_test.cc b/db/perf_context_test.cc
@@ -188,6 +188,7 @@ TEST_F(PerfContextTest, StopWatchOverhead) {
   std::vector<uint64_t> timings(kTotalIterations);
 
   StopWatch timer(SystemClock::Default().get(), nullptr,
+                  Histograms::HISTOGRAM_ENUM_MAX,
                   Histograms::HISTOGRAM_ENUM_MAX, &elapsed);
   for (auto& timing : timings) {
     timing = elapsed;

diff --git a/file/random_access_file_reader.cc b/file/random_access_file_reader.cc
@@ -22,7 +22,7 @@
 #include "util/rate_limiter.h"
 
 namespace ROCKSDB_NAMESPACE {
-std::array<Histograms, std::size_t(IOActivity::kIOActivityTotal)>
+const std::array<Histograms, std::size_t(IOActivity::kIOActivityTotal)>
     kReadHistograms{{
         SST_READ_FLUSH_MICROS, SST_READ_COMPACTION_MICROS,
         BLOB_DB_BLOB_FILE_READ_MICROS,
@@ -104,15 +104,12 @@ IOStatus RandomAccessFileReader::Read(const IOOptions& opts, uint64_t offset,
   {
     IOActivity io_activity_to_use =
         op_io_activity != IOActivity::kUnknown ? op_io_activity : io_activity_;
-    StopWatch sw_sst_read_mircos(
-        clock_, stats_, SST_READ_MICROS,
-        (stats_ != nullptr && (io_activity_to_use == IOActivity::kCompaction ||
-                               io_activity_to_use == IOActivity::kFlush))
-            ? &elapsed
-            : nullptr,
-        true /*overwrite*/, true /*delay_enabled*/);
     StopWatch sw(clock_, stats_,
                  kReadHistograms[(std::size_t)(io_activity_to_use)],
+                 (io_activity_to_use == IOActivity::kCompaction ||
+                  io_activity_to_use == IOActivity::kFlush)
+                     ? SST_READ_MICROS
+                     : Histograms::HISTOGRAM_ENUM_MAX,
                  (stats_ != nullptr) ? &elapsed : nullptr, true /*overwrite*/,
                  true /*delay_enabled*/);
     auto prev_perf_level = GetPerfLevel();
@@ -309,15 +306,12 @@ IOStatus RandomAccessFileReader::MultiRead(
   {
     IOActivity io_activity_to_use =
         op_io_activity != IOActivity::kUnknown ? op_io_activity : io_activity_;
-    StopWatch sw_sst_read_mircos(
-        clock_, stats_, SST_READ_MICROS,
-        (stats_ != nullptr && (io_activity_to_use == IOActivity::kCompaction ||
-                               io_activity_to_use == IOActivity::kFlush))
-            ? &elapsed
-            : nullptr,
-        true /*overwrite*/, true /*delay_enabled*/);
     StopWatch sw(clock_, stats_,
                  kReadHistograms[(std::size_t)(io_activity_to_use)],
+                 (io_activity_to_use == IOActivity::kCompaction ||
+                  io_activity_to_use == IOActivity::kFlush)
+                     ? SST_READ_MICROS
+                     : Histograms::HISTOGRAM_ENUM_MAX,
                  (stats_ != nullptr) ? &elapsed : nullptr, true /*overwrite*/,
                  true /*delay_enabled*/);
     auto prev_perf_level = GetPerfLevel();
@@ -506,12 +500,14 @@ IOStatus RandomAccessFileReader::ReadAsync(
 
     assert(read_async_info->buf_.CurrentSize() == 0);
 
-    StopWatch sw(clock_, nullptr /*stats*/, DB_GET /*hist_type*/, &elapsed,
+    StopWatch sw(clock_, nullptr /*stats*/, DB_GET /*hist_type_1*/,
+                 Histograms::HISTOGRAM_ENUM_MAX /*hist_type_2*/, &elapsed,
                  true /*overwrite*/, true /*delay_enabled*/);
     s = file_->ReadAsync(aligned_req, opts, read_async_callback,
                          read_async_info, io_handle, del_fn, nullptr /*dbg*/);
   } else {
-    StopWatch sw(clock_, nullptr /*stats*/, DB_GET /*hist_type*/, &elapsed,
+    StopWatch sw(clock_, nullptr /*stats*/, DB_GET /*hist_type_1*/,
+                 Histograms::HISTOGRAM_ENUM_MAX /*hist_type_2*/, &elapsed,
                  true /*overwrite*/, true /*delay_enabled*/);
     s = file_->ReadAsync(req, opts, read_async_callback, read_async_info,
                          io_handle, del_fn, nullptr /*dbg*/);

diff --git a/util/stop_watch.h b/util/stop_watch.h
@@ -9,23 +9,28 @@
 
 namespace ROCKSDB_NAMESPACE {
 // Auto-scoped.
-// Records the measure time into the corresponding histogram if statistics
+// Records the measure time into the corresponding histogram(s) if statistics
 // is not nullptr. It is also saved into *elapsed if the pointer is not nullptr
 // and overwrite is true, it will be added to *elapsed if overwrite is false.
 class StopWatch {
  public:
   StopWatch(SystemClock* clock, Statistics* statistics,
-            const uint32_t hist_type, uint64_t* elapsed = nullptr,
-            bool overwrite = true, bool delay_enabled = false)
+            const uint32_t hist_type_1,
+            const uint32_t hist_type_2 = Histograms::HISTOGRAM_ENUM_MAX,
+            uint64_t* elapsed = nullptr, bool overwrite = true,
+            bool delay_enabled = false)
       : clock_(clock),
         statistics_(statistics),
-        hist_type_(hist_type),
+        hist_type_1_(hist_type_1),
+        hist_type_2_(hist_type_2),
         elapsed_(elapsed),
         overwrite_(overwrite),
         stats_enabled_(statistics &&
                        statistics->get_stats_level() >=
                            StatsLevel::kExceptTimers &&
-                       statistics->HistEnabledForType(hist_type)),
+                       statistics->HistEnabledForType(hist_type_1) &&
+                       (hist_type_2 == Histograms::HISTOGRAM_ENUM_MAX ||
+                        statistics->HistEnabledForType(hist_type_2))),
         delay_enabled_(delay_enabled),
         total_delay_(0),
         delay_start_time_(0),
@@ -44,10 +49,13 @@ class StopWatch {
       *elapsed_ -= total_delay_;
     }
     if (stats_enabled_) {
-      statistics_->reportTimeToHistogram(
-          hist_type_, (elapsed_ != nullptr)
-                          ? *elapsed_
-                          : (clock_->NowMicros() - start_time_));
+      const auto time = (elapsed_ != nullptr)
+                            ? *elapsed_
+                            : (clock_->NowMicros() - start_time_);
+      statistics_->reportTimeToHistogram(hist_type_1_, time);
+      if (hist_type_2_ != Histograms::HISTOGRAM_ENUM_MAX) {
+        statistics_->reportTimeToHistogram(hist_type_2_, time);
+      }
     }
   }
 
@@ -75,7 +83,8 @@ class StopWatch {
  private:
   SystemClock* clock_;
   Statistics* statistics_;
-  const uint32_t hist_type_;
+  const uint32_t hist_type_1_;
+  const uint32_t hist_type_2_;
   uint64_t* elapsed_;
   bool overwrite_;
   bool stats_enabled_;