From 7dc1276afe140546f97cff56f2e0df1dc1d3d58f Mon Sep 17 00:00:00 2001
From: Alexey Milovidov <milovidov@yandex-team.ru>
Date: Sun, 8 Jul 2018 08:26:51 +0300
Subject: [PATCH] Little better #2281

---
 .../src/Storages/MergeTree/DiskSpaceMonitor.h | 26 +++++++++----------
 dbms/src/Storages/StorageMergeTree.cpp        |  3 +--
 .../Storages/StorageReplicatedMergeTree.cpp   |  3 +--
 3 files changed, 15 insertions(+), 17 deletions(-)

diff --git a/dbms/src/Storages/MergeTree/DiskSpaceMonitor.h b/dbms/src/Storages/MergeTree/DiskSpaceMonitor.h
index d6e22e22acc..d06d25598c3 100644
--- a/dbms/src/Storages/MergeTree/DiskSpaceMonitor.h
+++ b/dbms/src/Storages/MergeTree/DiskSpaceMonitor.h
@@ -68,7 +68,7 @@ public:
         }
 
         /// Change amount of reserved space. When new_size is greater than before, availability of free space is not checked.
-        void update(size_t new_size)
+        void update(UInt64 new_size)
         {
             std::lock_guard<std::mutex> lock(DiskSpaceMonitor::mutex);
             DiskSpaceMonitor::reserved_bytes -= size;
@@ -76,12 +76,12 @@ public:
             DiskSpaceMonitor::reserved_bytes += size;
         }
 
-        size_t getSize() const
+        UInt64 getSize() const
         {
             return size;
         }
 
-        Reservation(size_t size_)
+        Reservation(UInt64 size_)
             : size(size_), metric_increment(CurrentMetrics::DiskSpaceReservedForMerge, size)
         {
             std::lock_guard<std::mutex> lock(DiskSpaceMonitor::mutex);
@@ -90,23 +90,23 @@ public:
         }
 
     private:
-        size_t size;
+        UInt64 size;
         CurrentMetrics::Increment metric_increment;
     };
 
     using ReservationPtr = std::unique_ptr<Reservation>;
 
-    static size_t getUnreservedFreeSpace(const std::string & path)
+    static UInt64 getUnreservedFreeSpace(const std::string & path)
     {
         struct statvfs fs;
 
         if (statvfs(path.c_str(), &fs) != 0)
             throwFromErrno("Could not calculate available disk space (statvfs)", ErrorCodes::CANNOT_STATVFS);
 
-        size_t res = fs.f_bfree * fs.f_bsize;
+        UInt64 res = fs.f_bfree * fs.f_bsize;
 
         /// Heuristic by Michael Kolupaev: reserve 30 MB more, because statvfs shows few megabytes more space than df.
-        res -= std::min(res, static_cast<size_t>(30 * (1ul << 20)));
+        res -= std::min(res, static_cast<UInt64>(30 * (1ul << 20)));
 
         std::lock_guard<std::mutex> lock(mutex);
 
@@ -118,22 +118,22 @@ public:
         return res;
     }
 
-    static size_t getReservedSpace()
+    static UInt64 getReservedSpace()
     {
         std::lock_guard<std::mutex> lock(mutex);
         return reserved_bytes;
     }
 
-    static size_t getReservationCount()
+    static UInt64 getReservationCount()
     {
         std::lock_guard<std::mutex> lock(mutex);
         return reservation_count;
     }
 
     /// If not enough (approximately) space, throw an exception.
-    static ReservationPtr reserve(const std::string & path, size_t size)
+    static ReservationPtr reserve(const std::string & path, UInt64 size)
     {
-        size_t free_bytes = getUnreservedFreeSpace(path);
+        UInt64 free_bytes = getUnreservedFreeSpace(path);
         if (free_bytes < size)
             throw Exception("Not enough free disk space to reserve: " + formatReadableSizeWithBinarySuffix(free_bytes) + " available, "
                 + formatReadableSizeWithBinarySuffix(size) + " requested", ErrorCodes::NOT_ENOUGH_SPACE);
@@ -141,8 +141,8 @@ public:
     }
 
 private:
-    static size_t reserved_bytes;
-    static size_t reservation_count;
+    static UInt64 reserved_bytes;
+    static UInt64 reservation_count;
     static std::mutex mutex;
 };
 
diff --git a/dbms/src/Storages/StorageMergeTree.cpp b/dbms/src/Storages/StorageMergeTree.cpp
index d2ba37e6992..ac14e1ccd97 100644
--- a/dbms/src/Storages/StorageMergeTree.cpp
+++ b/dbms/src/Storages/StorageMergeTree.cpp
@@ -301,8 +301,6 @@ bool StorageMergeTree::merge(
 
     auto structure_lock = lockStructure(true, __PRETTY_FUNCTION__);
 
-    size_t disk_space = DiskSpaceMonitor::getUnreservedFreeSpace(full_path);
-
     MergeTreeDataMergerMutator::FuturePart future_part;
 
     /// You must call destructor with unlocked `currently_merging_mutex`.
@@ -326,6 +324,7 @@ bool StorageMergeTree::merge(
         }
         else
         {
+            UInt64 disk_space = DiskSpaceMonitor::getUnreservedFreeSpace(full_path);
             selected = merger.selectAllPartsToMergeWithinPartition(future_part, disk_space, can_merge, partition_id, final, out_disable_reason);
         }
 
diff --git a/dbms/src/Storages/StorageReplicatedMergeTree.cpp b/dbms/src/Storages/StorageReplicatedMergeTree.cpp
index 75d57210610..c7523aad693 100644
--- a/dbms/src/Storages/StorageReplicatedMergeTree.cpp
+++ b/dbms/src/Storages/StorageReplicatedMergeTree.cpp
@@ -2904,8 +2904,6 @@ bool StorageReplicatedMergeTree::optimize(const ASTPtr & query, const ASTPtr & p
         /// (merge_selecting_thread or OPTIMIZE queries) could assign new merges.
         std::lock_guard<std::mutex> merge_selecting_lock(merge_selecting_mutex);
 
-        size_t disk_space = DiskSpaceMonitor::getUnreservedFreeSpace(full_path);
-
         MergeTreeDataMergerMutator::FuturePart future_merged_part;
         String disable_reason;
         bool selected = false;
@@ -2923,6 +2921,7 @@ bool StorageReplicatedMergeTree::optimize(const ASTPtr & query, const ASTPtr & p
         }
         else
         {
+            UInt64 disk_space = DiskSpaceMonitor::getUnreservedFreeSpace(full_path);
             String partition_id = data.getPartitionIDFromQuery(partition, context);
             selected = merger_mutator.selectAllPartsToMergeWithinPartition(
                 future_merged_part, disk_space, can_merge, partition_id, final, &disable_reason);