Rename a recently added PerfContext counter (#11294)

Summary:
The patch renames the counter added in https://github.com/facebook/rocksdb/issues/11284 for better consistency with the existing naming scheme.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/11294

Test Plan: `make check`

Reviewed By: jowlyzhang

Differential Revision: D44035964

Pulled By: ltamasi

fbshipit-source-id: 8b1a2a03ee728148365367e0ecc1fcf462f62191

HISTORY.md

@@ -10,7 +10,7 @@
 
 ### New Features
 * Add statistics rocksdb.secondary.cache.filter.hits, rocksdb.secondary.cache.index.hits, and rocksdb.secondary.cache.filter.hits
-* Added a new PerfContext counter `internal_merge_count_point_lookups` which tracks the number of Merge operands applied while serving point lookup queries.
+* Added a new PerfContext counter `internal_merge_point_lookup_count` which tracks the number of Merge operands applied while serving point lookup queries.
 
 ## 8.0.0 (02/19/2023)
 ### Behavior changes

db/memtable.cc

@@ -1230,7 +1230,7 @@ static bool SaveValue(void* arg, const char* entry) {
         *(s->merge_in_progress) = true;
         merge_context->PushOperand(
             v, s->inplace_update_support == false /* operand_pinned */);
-        PERF_COUNTER_ADD(internal_merge_count_point_lookups, 1);
+        PERF_COUNTER_ADD(internal_merge_point_lookup_count, 1);
 
         if (s->do_merge && merge_operator->ShouldMerge(
                                merge_context->GetOperandsDirectionBackward())) {

db/perf_context_test.cc

@@ -1018,8 +1018,7 @@ TEST_F(PerfContextTest, MergeOperandCount) {
         PinnableSlice result;
         ASSERT_OK(db->Get(ReadOptions(), db->DefaultColumnFamily(), keys[i],
                           &result));
-        ASSERT_EQ(get_perf_context()->internal_merge_count_point_lookups,
-                  i + 1);
+        ASSERT_EQ(get_perf_context()->internal_merge_point_lookup_count, i + 1);
 
         get_perf_context()->Reset();
       }
@@ -1029,8 +1028,7 @@ TEST_F(PerfContextTest, MergeOperandCount) {
         PinnableWideColumns result;
         ASSERT_OK(db->GetEntity(ReadOptions(), db->DefaultColumnFamily(),
                                 keys[i], &result));
-        ASSERT_EQ(get_perf_context()->internal_merge_count_point_lookups,
-                  i + 1);
+        ASSERT_EQ(get_perf_context()->internal_merge_point_lookup_count, i + 1);
 
         get_perf_context()->Reset();
       }
@@ -1056,7 +1054,7 @@ TEST_F(PerfContextTest, MergeOperandCount) {
           ASSERT_OK(statuses[i]);
         }
 
-        ASSERT_EQ(get_perf_context()->internal_merge_count_point_lookups,
+        ASSERT_EQ(get_perf_context()->internal_merge_point_lookup_count,
                   total_merges);
 
         get_perf_context()->Reset();
@@ -1074,7 +1072,7 @@ TEST_F(PerfContextTest, MergeOperandCount) {
           ASSERT_OK(statuses[i]);
         }
 
-        ASSERT_EQ(get_perf_context()->internal_merge_count_point_lookups,
+        ASSERT_EQ(get_perf_context()->internal_merge_point_lookup_count,
                   total_merges);
 
         get_perf_context()->Reset();

include/rocksdb/perf_context.h

@@ -142,7 +142,7 @@ struct PerfContext {
   // How many merge operands were fed into the merge operator by point lookups.
   // Note: base values are not included in the count.
   //
-  uint64_t internal_merge_count_point_lookups;
+  uint64_t internal_merge_point_lookup_count;
   // Number of times we reseeked inside a merging iterator, specifically to skip
   // after or before a range of keys covered by a range deletion in a newer LSM
   // component.

monitoring/perf_context.cc

@@ -69,7 +69,7 @@ PerfContext::PerfContext(const PerfContext& other) {
   internal_delete_skipped_count = other.internal_delete_skipped_count;
   internal_recent_skipped_count = other.internal_recent_skipped_count;
   internal_merge_count = other.internal_merge_count;
-  internal_merge_count_point_lookups = other.internal_merge_count_point_lookups;
+  internal_merge_point_lookup_count = other.internal_merge_point_lookup_count;
   internal_range_del_reseek_count = other.internal_range_del_reseek_count;
   write_wal_time = other.write_wal_time;
   get_snapshot_time = other.get_snapshot_time;
@@ -189,7 +189,7 @@ PerfContext::PerfContext(PerfContext&& other) noexcept {
   internal_delete_skipped_count = other.internal_delete_skipped_count;
   internal_recent_skipped_count = other.internal_recent_skipped_count;
   internal_merge_count = other.internal_merge_count;
-  internal_merge_count_point_lookups = other.internal_merge_count_point_lookups;
+  internal_merge_point_lookup_count = other.internal_merge_point_lookup_count;
   internal_range_del_reseek_count = other.internal_range_del_reseek_count;
   write_wal_time = other.write_wal_time;
   get_snapshot_time = other.get_snapshot_time;
@@ -311,7 +311,7 @@ PerfContext& PerfContext::operator=(const PerfContext& other) {
   internal_delete_skipped_count = other.internal_delete_skipped_count;
   internal_recent_skipped_count = other.internal_recent_skipped_count;
   internal_merge_count = other.internal_merge_count;
-  internal_merge_count_point_lookups = other.internal_merge_count_point_lookups;
+  internal_merge_point_lookup_count = other.internal_merge_point_lookup_count;
   internal_range_del_reseek_count = other.internal_range_del_reseek_count;
   write_wal_time = other.write_wal_time;
   get_snapshot_time = other.get_snapshot_time;
@@ -425,7 +425,7 @@ void PerfContext::Reset() {
   internal_delete_skipped_count = 0;
   internal_recent_skipped_count = 0;
   internal_merge_count = 0;
-  internal_merge_count_point_lookups = 0;
+  internal_merge_point_lookup_count = 0;
   internal_range_del_reseek_count = 0;
   write_wal_time = 0;
 
@@ -560,7 +560,7 @@ std::string PerfContext::ToString(bool exclude_zero_counters) const {
   PERF_CONTEXT_OUTPUT(internal_delete_skipped_count);
   PERF_CONTEXT_OUTPUT(internal_recent_skipped_count);
   PERF_CONTEXT_OUTPUT(internal_merge_count);
-  PERF_CONTEXT_OUTPUT(internal_merge_count_point_lookups);
+  PERF_CONTEXT_OUTPUT(internal_merge_point_lookup_count);
   PERF_CONTEXT_OUTPUT(internal_range_del_reseek_count);
   PERF_CONTEXT_OUTPUT(write_wal_time);
   PERF_CONTEXT_OUTPUT(get_snapshot_time);

table/get_context.cc

@@ -442,7 +442,7 @@ bool GetContext::SaveValue(const ParsedInternalKey& parsed_key,
         state_ = kMerge;
         // value_pinner is not set from plain_table_reader.cc for example.
         push_operand(value, value_pinner);
-        PERF_COUNTER_ADD(internal_merge_count_point_lookups, 1);
+        PERF_COUNTER_ADD(internal_merge_point_lookup_count, 1);
 
         if (do_merge_ && merge_operator_ != nullptr &&
             merge_operator_->ShouldMerge(