Revert "[RFC] Fix memory tracking with min_bytes_to_use_mmap_io"

src/IO/MMapReadBufferFromFileWithCache.cpp

@@ -1,5 +1,4 @@
 #include <IO/MMapReadBufferFromFileWithCache.h>
-#include <Common/CurrentMemoryTracker.h>
 
 
 namespace DB
@@ -75,16 +74,4 @@ off_t MMapReadBufferFromFileWithCache::seek(off_t offset, int whence)
     return new_pos;
 }
 
-void MMapReadBufferFromFileWithCache::track(size_t bytes_)
-{
-    CurrentMemoryTracker::alloc(bytes_);
-    tracked_bytes = bytes_;
-}
-
-MMapReadBufferFromFileWithCache::~MMapReadBufferFromFileWithCache()
-{
-    if (tracked_bytes)
-        CurrentMemoryTracker::free(tracked_bytes);
-}
-
 }

src/IO/MMapReadBufferFromFileWithCache.h

@@ -16,27 +16,13 @@ public:
     /// Map till end of file.
     MMapReadBufferFromFileWithCache(MMappedFileCache & cache, const std::string & file_name, size_t offset);
 
-    ~MMapReadBufferFromFileWithCache() override;
-
     off_t getPosition() override;
     std::string getFileName() const override;
     off_t seek(off_t offset, int whence) override;
 
-    /// Track memory with MemoryTracker.
-    ///
-    /// NOTE: that this is not the size of mmap() region, but estimated size of
-    /// data that will be read (see MergeTreeReaderStream).
-    /// And from one point of view it should not be accounted here, since the
-    /// kernel may unmap physical pages, but in practice firstly it will mmap it,
-    /// RSS will grow, total_memory_tracker will be synced with RSS and the
-    /// allocations will start to fail.
-    void track(size_t bytes_);
-
 private:
     MMappedFileCache::MappedPtr mapped;
 
-    size_t tracked_bytes = 0;
-
     void init();
 };
 

src/IO/createReadBufferFromFileBase.cpp

@@ -50,7 +50,6 @@ std::unique_ptr<ReadBufferFromFileBase> createReadBufferFromFileBase(
         try
         {
             auto res = std::make_unique<MMapReadBufferFromFileWithCache>(*mmap_cache, filename_, 0);
-            res->track(estimated_size);
             ProfileEvents::increment(ProfileEvents::CreatedReadBufferMMap);
             return res;
         }

tests/queries/0_stateless/01605_adaptive_granularity_block_borders.sql

@@ -23,6 +23,6 @@ SELECT marks FROM system.parts WHERE table = 'adaptive_table' and database=curre
 -- If we have computed granularity incorrectly than we will exceed this limit.
 SET max_memory_usage='30M';
 
-SELECT max(length(value)) FROM adaptive_table SETTINGS min_bytes_to_use_mmap_io=0;
+SELECT max(length(value)) FROM adaptive_table;
 
 DROP TABLE IF EXISTS adaptive_table;

tests/queries/0_stateless/01818_min_bytes_to_use_mmap_io_memory_tracking.sql

@@ -1,5 +0,0 @@
-drop table if exists data_01818;
-
-create table data_01818 (key Int, value String) engine=MergeTree() order by key settings min_bytes_for_wide_part=0 as select number, randomPrintableASCII(100) from numbers(1e6);
-select * from data_01818 format Null settings min_bytes_to_use_mmap_io=1, max_memory_usage='20Mi', max_threads=1; -- { serverError 241 }
-select * from data_01818 format Null settings min_bytes_to_use_mmap_io=1e9, max_memory_usage='20Mi', max_threads=1;

tests/queries/1_stateful/00084_external_aggregation.sql

@@ -2,8 +2,6 @@ SET max_bytes_before_external_group_by = 200000000;
 
 SET max_memory_usage = 1500000000;
 SET max_threads = 12;
-SET min_bytes_to_use_mmap_io = 0;
-
 SELECT URL, uniq(SearchPhrase) AS u FROM test.hits GROUP BY URL ORDER BY u DESC, URL LIMIT 10;
 
 SET max_memory_usage = 300000000;