Experiment with CLOCK_THREAD_CPUTIME_ID

ConflictSet.cpp

@@ -29,6 +29,7 @@ limitations under the License.
 #include <span>
 #include <string>
 #include <string_view>
+#include <sys/time.h>
 #include <type_traits>
 #include <utility>
 
@@ -3067,9 +3068,15 @@ Node *firstGeqPhysical(Node *n, const std::span<const uint8_t> key) {
   }
 }
 
+#define MEASURE_CHECK_CPU_TIME 0
+
 struct __attribute__((visibility("hidden"))) ConflictSet::Impl {
 
   void check(const ReadRange *reads, Result *result, int count) {
+#if MEASURE_CHECK_CPU_TIME
+    timespec ts_begin;
+    clock_gettime(CLOCK_THREAD_CPUTIME_ID, &ts_begin);
+#endif
     int commits_accum = 0;
     int conflicts_accum = 0;
     int too_olds_accum = 0;
@@ -3115,6 +3122,13 @@ struct __attribute__((visibility("hidden"))) ConflictSet::Impl {
     conflicts_total.add(conflicts_accum);
     too_olds_total.add(too_olds_accum);
     check_bytes_total.add(check_byte_accum);
+#if MEASURE_CHECK_CPU_TIME
+    timespec ts_end;
+    clock_gettime(CLOCK_THREAD_CPUTIME_ID, &ts_end);
+    check_cpu_seconds_total.add(
+        std::max<double>(0, (ts_end.tv_nsec * 1e-9 + ts_end.tv_sec) -
+                                (ts_begin.tv_nsec * 1e-9 + ts_begin.tv_sec)));
+#endif
   }
 
   void addWrites(const WriteRange *writes, int count, int64_t writeVersion) {
@@ -3329,6 +3343,10 @@ struct __attribute__((visibility("hidden"))) ConflictSet::Impl {
   COUNTER(too_olds_total,
           "Total number of checks where the result is \"too old\"");
   COUNTER(check_bytes_total, "Total number of key bytes checked");
+#if MEASURE_CHECK_CPU_TIME
+  COUNTER(check_cpu_seconds_total,
+          "Total cpu seconds spent in a call to check");
+#endif
   // ==================== END METRICS DEFINITIONS ====================
 #undef GAUGE
 #undef COUNTER