Add memory usage and some "check" metrics

ConflictSet.cpp

@@ -1715,11 +1715,17 @@ struct SearchStepWise {
   }
 };
 
+void onPointRead(ConflictSet::Impl *impl);
+void onPrefixRead(ConflictSet::Impl *impl);
+void onRangeRead(ConflictSet::Impl *impl);
+void onCheckMaxBetween(ConflictSet::Impl *impl);
+
 // Logically this is the same as performing firstGeq and then checking against
 // point or range version according to cmp, but this version short circuits as
 // soon as it can prove that there's no conflict.
 bool checkPointRead(Node *n, const std::span<const uint8_t> key,
                     InternalVersionT readVersion, ConflictSet::Impl *impl) {
+  onPointRead(impl);
 #if DEBUG_VERBOSE && !defined(NDEBUG)
   fprintf(stderr, "Check point read: %s\n", printable(key).c_str());
 #endif
@@ -1797,6 +1803,7 @@ downLeftSpine:
 // short circuits as soon as it can prove that there's no conflict.
 bool checkPrefixRead(Node *n, const std::span<const uint8_t> key,
                      InternalVersionT readVersion, ConflictSet::Impl *impl) {
+  onPrefixRead(impl);
 #if DEBUG_VERBOSE && !defined(NDEBUG)
   fprintf(stderr, "Check prefix read: %s\n", printable(key).c_str());
 #endif
@@ -2312,6 +2319,7 @@ bool checkRangeStartsWith(Node *n, std::span<const uint8_t> key, int begin,
 #endif
   auto remaining = key;
   if (remaining.size() == 0) {
+    onCheckMaxBetween(impl);
     return checkMaxBetweenExclusive<kAVX512>(n, begin, end, readVersion);
   }
 
@@ -2408,6 +2416,7 @@ template <bool kAVX512> struct CheckRangeLeftSide {
     }
 
     if (searchPathLen >= prefixLen) {
+      onCheckMaxBetween(impl);
       if (!checkMaxBetweenExclusive<kAVX512>(n, remaining[0], 256,
                                              readVersion)) {
         ok = false;
@@ -2538,6 +2547,7 @@ template <bool kAVX512> struct CheckRangeRightSide {
         return true;
       }
 
+      onCheckMaxBetween(impl);
       if (!checkMaxBetweenExclusive<kAVX512>(n, -1, remaining[0],
                                              readVersion)) {
         ok = false;
@@ -2635,6 +2645,7 @@ template <bool kAVX512>
 bool checkRangeReadImpl(Node *n, std::span<const uint8_t> begin,
                         std::span<const uint8_t> end,
                         InternalVersionT readVersion, ConflictSet::Impl *impl) {
+  onRangeRead(impl);
   int lcp = longestCommonPrefix(begin.data(), end.data(),
                                 std::min(begin.size(), end.size()));
   if (lcp == int(begin.size()) && end.size() == begin.size() + 1 &&
@@ -3068,6 +3079,10 @@ struct __attribute__((visibility("hidden"))) ConflictSet::Impl {
               ? Commit
               : Conflict;
     }
+    read_point_total.add(std::exchange(accume_point_read, 0));
+    read_prefix_total.add(std::exchange(accume_prefix_read, 0));
+    read_range_total.add(std::exchange(accume_range_read, 0));
+    read_range_node_total.add(std::exchange(accume_max_between, 0));
   }
 
   void addWrites(const WriteRange *writes, int count, int64_t writeVersion) {
@@ -3101,6 +3116,8 @@ struct __attribute__((visibility("hidden"))) ConflictSet::Impl {
                       this);
       }
     }
+
+    memory_bytes.set(totalBytes);
   }
 
   // Spends up to `fuel` gc'ing, and returns its unused fuel. Reclaims memory
@@ -3170,6 +3187,8 @@ struct __attribute__((visibility("hidden"))) ConflictSet::Impl {
     }
 #endif
     keyUpdates = gcScanStep(keyUpdates);
+
+    memory_bytes.set(totalBytes);
   }
 
   int64_t getBytes() const { return totalBytes; }
@@ -3283,6 +3302,17 @@ struct __attribute__((visibility("hidden"))) ConflictSet::Impl {
           "Total number of nodes of type \"Node48\" that have been released");
   COUNTER(node256_released_total,
           "Total number of nodes of type \"Node256\" that have been released");
+  GAUGE(memory_bytes, "Total number of bytes in use.");
+  double accume_point_read = 0;
+  COUNTER(read_point_total, "Total number of point reads checked.");
+  double accume_prefix_read = 0;
+  COUNTER(read_prefix_total, "Total number of prefix reads checked.");
+  double accume_range_read = 0;
+  COUNTER(read_range_total, "Total number of range reads checked.");
+  double accume_max_between = 0;
+  COUNTER(read_range_node_total,
+          "Total number of range checks of individual nodes while "
+          "checking a range read.");
   // ==================== END METRICS DEFINITIONS ====================
 #undef GAUGE
 #undef COUNTER
@@ -3334,6 +3364,11 @@ InternalVersionT maxVersion(Node *n, ConflictSet::Impl *impl) {
   }
 }
 
+void onPointRead(ConflictSet::Impl *impl) { ++impl->accume_point_read; }
+void onPrefixRead(ConflictSet::Impl *impl) { ++impl->accume_prefix_read; }
+void onRangeRead(ConflictSet::Impl *impl) { ++impl->accume_range_read; }
+void onCheckMaxBetween(ConflictSet::Impl *impl) { ++impl->accume_max_between; }
+
 void setMaxVersion(Node *n, ConflictSet::Impl *impl, InternalVersionT newMax) {
   int index = n->parentsIndex;
   n = n->parent;