Removed code for freezing partitions due to unacceptable implementation [#METR-20656].

dbms/include/DB/Storages/MergeTree/MergeTreeDataMerger.h

@@ -63,9 +63,6 @@ public:
 	/// Примерное количество места на диске, нужное для мерджа. С запасом.
 	static size_t estimateDiskSpaceForMerge(const MergeTreeData::DataPartsVector & parts);
 
-	void freezePartition(const std::string & partition);
-	void unfreezePartition(const std::string & partition);
-
 	/** Отменяет все мерджи. Все выполняющиеся сейчас вызовы mergeParts скоро бросят исключение.
 	  * Все новые вызовы будут бросать исключения, пока не будет вызван uncancel().
 	  */
@@ -79,7 +76,6 @@ private:
 	/** Выбрать все куски принадлежащие одной партиции.
 	  */
 	MergeTreeData::DataPartsVector selectAllPartsFromPartition(DayNum_t partition);
-	bool isPartitionFrozen(const MergeTreeData::DataPart & part) const;
 
 private:
 	using FrozenPartitions = std::unordered_set<DayNum_t>;
@@ -92,9 +88,6 @@ private:
 	/// Когда в последний раз писали в лог, что место на диске кончилось (чтобы не писать об этом слишком часто).
 	time_t disk_space_warning_time = 0;
 
-	std::mutex freeze_lock;
-	FrozenPartitions frozen_partitions;
-
 	CancellationHook cancellation_hook;
 
 	std::atomic<bool> cancelled {false};

dbms/include/DB/Storages/MergeTree/ReshardingWorker.h

@@ -294,16 +294,6 @@ private:
 	zkutil::SingleBarrier getElectionBarrier();
 	zkutil::SingleBarrier getCommitBarrier();
 
-	/// Prevent merging jobs from being performed on the partition that we
-	/// want to reshard on the current host. This operation is persistent:
-	/// even if a node failure occurred, a partition remains frozen as long
-	/// as it is not unfrozen explicitely. So use it with care as regards
-	/// exceptions.
-	void freezeSourcePartition();
-
-	/// Make the partition that we want to reshard available for merging jobs.
-	void unfreezeSourcePartition();
-
 	/// Get the ZooKeeper path of a given coordinator.
 	std::string getCoordinatorPath(const std::string & coordinator_id) const;
 	/// Get the ZooKeeper path of a given job partition.

dbms/src/Storages/MergeTree/MergeTreeDataMerger.cpp

@@ -83,19 +83,6 @@ bool MergeTreeDataMerger::selectPartsToMerge(MergeTreeData::DataPartsVector & pa
 {
 	MergeTreeData::DataParts data_parts = data.getDataParts();
 
-	{
-		std::lock_guard<std::mutex> guard{freeze_lock};
-
-		for (auto it = data_parts.begin(); it != data_parts.end(); )
-		{
-			const MergeTreeData::DataPartPtr & part = *it;
-			if (isPartitionFrozen(*part))
-				it = data_parts.erase(it);
-			else
-				++it;
-		}
-	}
-
 	if (data_parts.empty())
 		return false;
 
@@ -351,28 +338,6 @@ MergeTreeData::DataPartPtr MergeTreeDataMerger::mergeParts(
 	size_t aio_threshold, MergeTreeData::Transaction * out_transaction,
 	DiskSpaceMonitor::Reservation * disk_reservation)
 {
-	std::lock_guard<std::mutex> guard{freeze_lock};
-
-	if (!frozen_partitions.empty())
-	{
-		size_t old_parts_size = parts.size();
-
-		auto first_removed = std::remove_if(parts.begin(), parts.end(), [&](const MergeTreeData::DataPartPtr & part)
-		{
-			return isPartitionFrozen(*part);
-		});
-		parts.erase(first_removed, parts.end());
-
-		if (parts.empty())
-			throw Exception("All the chosen parts lie inside a frozen partition. Cancelling.", ErrorCodes::ABORTED);
-
-		if (disk_reservation && (parts.size() != old_parts_size))
-		{
-			size_t sum_parts_size_in_bytes = MergeTreeDataMerger::estimateDiskSpaceForMerge(parts);
-			disk_reservation = DiskSpaceMonitor::reserve(data.getFullPath(), sum_parts_size_in_bytes);
-		}
-	}
-
 	merge_entry->num_parts = parts.size();
 
 	LOG_DEBUG(log, "Merging " << parts.size() << " parts: from " << parts.front()->name << " to " << parts.back()->name << " into " << merged_name);
@@ -821,23 +786,6 @@ size_t MergeTreeDataMerger::estimateDiskSpaceForMerge(const MergeTreeData::DataP
 	return static_cast<size_t>(res * DISK_USAGE_COEFFICIENT_TO_RESERVE);
 }
 
-void MergeTreeDataMerger::freezePartition(const std::string & partition)
-{
-	std::lock_guard<std::mutex> guard{freeze_lock};
-	frozen_partitions.insert(MergeTreeData::getMonthFromName(partition));
-}
-
-void MergeTreeDataMerger::unfreezePartition(const std::string & partition)
-{
-	std::lock_guard<std::mutex> guard{freeze_lock};
-	frozen_partitions.erase(MergeTreeData::getMonthFromName(partition));
-}
-
-bool MergeTreeDataMerger::isPartitionFrozen(const MergeTreeData::DataPart & part) const
-{
-	return frozen_partitions.count(part.month);
-}
-
 void MergeTreeDataMerger::abortIfRequested()
 {
 	if (cancelled)

dbms/src/Storages/MergeTree/ReshardingWorker.cpp

@@ -593,9 +593,6 @@ void ReshardingWorker::perform(const std::string & job_descriptor, const std::st
 	auto & storage = typeid_cast<StorageReplicatedMergeTree &>(*(generic_storage.get()));
 	current_job.storage = &storage;
 
-	/// Protect the source partition from merging jobs.
-	freezeSourcePartition();
-
 	std::string dumped_coordinator_state;
 
 	auto handle_exception = [&](const std::string & cancel_msg, const std::string & error_msg)
@@ -623,7 +620,6 @@ void ReshardingWorker::perform(const std::string & job_descriptor, const std::st
 					dumped_coordinator_state = dumpCoordinatorState(current_job.coordinator_id);
 				}
 				deletion_lock.release();
-				unfreezeSourcePartition();
 				hardCleanup();
 			}
 		}
@@ -715,11 +711,11 @@ void ReshardingWorker::perform(const std::string & job_descriptor, const std::st
 			{
 				dumped_coordinator_state = dumpCoordinatorState(current_job.coordinator_id);
 				deletion_lock.release();
-				unfreezeSourcePartition();
 				hardCleanup();
 			}
 			else if (ex.code() == ErrorCodes::RESHARDING_COORDINATOR_DELETED)
-				unfreezeSourcePartition();
+			{
+			}
 			else if (ex.code() == ErrorCodes::RESHARDING_DISTRIBUTED_JOB_ON_HOLD)
 			{
 				/// The current distributed job is on hold and one or more required performers
@@ -757,9 +753,6 @@ void ReshardingWorker::perform(const std::string & job_descriptor, const std::st
 	}
 
 	deletion_lock.release();
-	/// Although the source partition has been dropped, the following function
-	/// must be called in order to delete all the data that makes freezing fail-safe.
-	unfreezeSourcePartition();
 	hardCleanup();
 
 	LOG_DEBUG(log, "Resharding job successfully completed.");
@@ -2505,25 +2498,6 @@ zkutil::SingleBarrier ReshardingWorker::getCommitBarrier()
 	return commit_barrier;
 }
 
-void ReshardingWorker::freezeSourcePartition()
-{
-	auto zookeeper = context.getZooKeeper();
-	auto & storage = *(current_job.storage);
-
-	zookeeper->createIfNotExists(storage.replica_path + "/frozen_partitions/"
-		+ current_job.partition, "");
-	storage.merger.freezePartition(current_job.partition);
-}
-
-void ReshardingWorker::unfreezeSourcePartition()
-{
-	auto zookeeper = context.getZooKeeper();
-	auto & storage = *(current_job.storage);
-
-	zookeeper->remove(storage.replica_path + "/frozen_partitions/" + current_job.partition);
-	storage.merger.unfreezePartition(current_job.partition);
-}
-
 std::string ReshardingWorker::getCoordinatorPath(const std::string & coordinator_id) const
 {
 	return coordination_path + "/" + coordinator_id;

dbms/src/Storages/StorageReplicatedMergeTree.cpp

@@ -293,11 +293,6 @@ StorageReplicatedMergeTree::StorageReplicatedMergeTree(
 
 	queue.pullLogsToQueue(current_zookeeper, nullptr);
 
-	/// Замораживаем партиции, которые прежне были в этом состоянии.
-	auto frozen_partitions = current_zookeeper->getChildren(replica_path + "/frozen_partitions");
-	for (const auto & partition : frozen_partitions)
-		merger.freezePartition(partition);
-
 	/// В этом потоке реплика будет активирована.
 	restarting_thread.reset(new ReplicatedMergeTreeRestartingThread(*this));
 }
@@ -315,9 +310,6 @@ void StorageReplicatedMergeTree::createNewZooKeeperNodes()
 	/// Отслеживание отставания реплик.
 	zookeeper->createIfNotExists(replica_path + "/min_unprocessed_insert_time", "");
 	zookeeper->createIfNotExists(replica_path + "/max_processed_insert_time", "");
-
-	/// Партиции, для которых временно не проводятся слияния.
-	zookeeper->createIfNotExists(replica_path + "/frozen_partitions", "");
 }