Merge pull request ClickHouse#60049 from ClickHouse/less-memory-usage…

…-primary-key

Maybe less memory usage for primary keys in memory

src/Storages/MergeTree/IMergeTreeDataPart.cpp

@@ -842,6 +842,7 @@ void IMergeTreeDataPart::loadIndex()
 
  for (size_t i = 0; i < key_size; ++i)
  {
+ loaded_index[i]->shrinkToFit();
  loaded_index[i]->protect();
  if (loaded_index[i]->size() != marks_count)
  throw Exception(ErrorCodes::CANNOT_READ_ALL_DATA, "Cannot read all data from index file {}(expected size: "

src/Storages/MergeTree/IMergeTreeDataPart.h

@@ -660,7 +660,7 @@ class IMergeTreeDataPart : public std::enable_shared_from_this<IMergeTreeDataPar
 
  virtual void appendFilesOfIndexGranularity(Strings & files) const;
 
- /// Loads index file.
+ /// Loads the index file.
  void loadIndex();
 
  void appendFilesOfIndex(Strings & files) const;

tests/queries/1_stateful/00098_primary_key_memory_allocated.reference

@@ -0,0 +1 @@
+1 1 1

tests/queries/1_stateful/00098_primary_key_memory_allocated.sql

@@ -0,0 +1 @@
+SELECT primary_key_bytes_in_memory < 16000, primary_key_bytes_in_memory_allocated < 16000, primary_key_bytes_in_memory_allocated / primary_key_bytes_in_memory < 1.1 FROM system.parts WHERE database = 'test' AND table = 'hits';