Turn off tasks stealing for remote disk

src/Storages/MergeTree/IMergeTreeDataPart.h

@@ -95,6 +95,8 @@ public:
 
     virtual bool isStoredOnDisk() const = 0;
 
+    virtual bool isStoredOnRemoteDisk() const = 0;
+
     virtual bool supportsVerticalMerge() const { return false; }
 
     /// NOTE: Returns zeros if column files are not found in checksums.

src/Storages/MergeTree/MergeTreeDataPartCompact.cpp

@@ -182,6 +182,11 @@ void MergeTreeDataPartCompact::checkConsistency(bool require_part_metadata) cons
     }
 }
 
+bool MergeTreeDataPartCompact::isStoredOnRemoteDisk() const
+{
+    return volume->getDisk()->isRemote();
+}
+
 MergeTreeDataPartCompact::~MergeTreeDataPartCompact()
 {
     removeIfNeeded();

src/Storages/MergeTree/MergeTreeDataPartCompact.h

@@ -56,6 +56,8 @@ public:
 
     bool isStoredOnDisk() const override { return true; }
 
+    bool isStoredOnRemoteDisk() const override;
+
     bool hasColumnFiles(const NameAndTypePair & column) const override;
 
     String getFileNameForColumn(const NameAndTypePair & /* column */) const override { return DATA_FILE_NAME; }

src/Storages/MergeTree/MergeTreeDataPartInMemory.h

@@ -44,6 +44,7 @@ public:
         const MergeTreeIndexGranularity & computed_index_granularity) const override;
 
     bool isStoredOnDisk() const override { return false; }
+    bool isStoredOnRemoteDisk() const override { return false; }
     bool hasColumnFiles(const NameAndTypePair & column) const override { return !!getColumnPosition(column.name); }
     String getFileNameForColumn(const NameAndTypePair & /* column */) const override { return ""; }
     void renameTo(const String & new_relative_path, bool remove_new_dir_if_exists) const override;

src/Storages/MergeTree/MergeTreeDataPartWide.cpp

@@ -142,6 +142,11 @@ void MergeTreeDataPartWide::loadIndexGranularity()
     index_granularity.setInitialized();
 }
 
+bool MergeTreeDataPartWide::isStoredOnRemoteDisk() const
+{
+    return volume->getDisk()->isRemote();
+}
+
 MergeTreeDataPartWide::~MergeTreeDataPartWide()
 {
     removeIfNeeded();

src/Storages/MergeTree/MergeTreeDataPartWide.h

@@ -50,6 +50,8 @@ public:
 
     bool isStoredOnDisk() const override { return true; }
 
+    bool isStoredOnRemoteDisk() const override;
+
     bool supportsVerticalMerge() const override { return true; }
 
     String getFileNameForColumn(const NameAndTypePair & column) const override;

src/Storages/MergeTree/MergeTreeReadPool.cpp

@@ -221,6 +221,10 @@ std::vector<size_t> MergeTreeReadPool::fillPerPartInfo(
     {
         const auto & part = parts[i];
 
+        /// Turn off tasks stealing in case there is remote disk.
+        if (part.data_part->isStoredOnRemoteDisk())
+            do_not_steal_tasks = true;
+
         /// Read marks for every data part.
         size_t sum_marks = 0;
         for (const auto & range : part.ranges)