ClickHouse/src/Storages/StorageMergeTree.h
2021-01-10 05:48:57 +03:00

251 lines
10 KiB
C++

#pragma once
#include <ext/shared_ptr_helper.h>
#include <Core/Names.h>
#include <Storages/AlterCommands.h>
#include <Storages/IStorage.h>
#include <Storages/MergeTree/MergeTreeData.h>
#include <Storages/MergeTree/MergeTreeDataSelectExecutor.h>
#include <Storages/MergeTree/MergeTreeDataWriter.h>
#include <Storages/MergeTree/MergeTreeDataMergerMutator.h>
#include <Storages/MergeTree/MergeTreePartsMover.h>
#include <Storages/MergeTree/MergeTreeMutationEntry.h>
#include <Storages/MergeTree/MergeTreeMutationStatus.h>
#include <Disks/StoragePolicy.h>
#include <Common/SimpleIncrement.h>
#include <Storages/MergeTree/BackgroundJobsExecutor.h>
namespace DB
{
/** See the description of the data structure in MergeTreeData.
*/
class StorageMergeTree final : public ext::shared_ptr_helper<StorageMergeTree>, public MergeTreeData
{
friend struct ext::shared_ptr_helper<StorageMergeTree>;
public:
void startup() override;
void shutdown() override;
~StorageMergeTree() override;
std::string getName() const override { return merging_params.getModeName() + "MergeTree"; }
bool supportsParallelInsert() const override { return true; }
bool supportsIndexForIn() const override { return true; }
Pipe read(
const Names & column_names,
const StorageMetadataPtr & /*metadata_snapshot*/,
SelectQueryInfo & query_info,
const Context & context,
QueryProcessingStage::Enum processed_stage,
size_t max_block_size,
unsigned num_streams) override;
void read(
QueryPlan & query_plan,
const Names & column_names,
const StorageMetadataPtr & /*metadata_snapshot*/,
SelectQueryInfo & query_info,
const Context & context,
QueryProcessingStage::Enum processed_stage,
size_t max_block_size,
unsigned num_streams) override;
std::optional<UInt64> totalRows(const Settings &) const override;
std::optional<UInt64> totalRowsByPartitionPredicate(const SelectQueryInfo &, const Context &) const override;
std::optional<UInt64> totalBytes(const Settings &) const override;
BlockOutputStreamPtr write(const ASTPtr & query, const StorageMetadataPtr & /*metadata_snapshot*/, const Context & context) override;
/** Perform the next step in combining the parts.
*/
bool optimize(
const ASTPtr & query,
const StorageMetadataPtr & /*metadata_snapshot*/,
const ASTPtr & partition,
bool final,
bool deduplicate,
const Names & deduplicate_by_columns,
const Context & context) override;
void mutate(const MutationCommands & commands, const Context & context) override;
/// Return introspection information about currently processing or recently processed mutations.
std::vector<MergeTreeMutationStatus> getMutationsStatus() const override;
CancellationCode killMutation(const String & mutation_id) override;
void drop() override;
void truncate(const ASTPtr &, const StorageMetadataPtr &, const Context &, TableExclusiveLockHolder &) override;
void alter(const AlterCommands & commands, const Context & context, TableLockHolder & table_lock_holder) override;
void checkTableCanBeDropped() const override;
ActionLock getActionLock(StorageActionBlockType action_type) override;
void onActionLockRemove(StorageActionBlockType action_type) override;
CheckResults checkData(const ASTPtr & query, const Context & context) override;
std::optional<JobAndPool> getDataProcessingJob() override;
private:
/// Mutex and condvar for synchronous mutations wait
std::mutex mutation_wait_mutex;
std::condition_variable mutation_wait_event;
MergeTreeDataSelectExecutor reader;
MergeTreeDataWriter writer;
MergeTreeDataMergerMutator merger_mutator;
BackgroundJobsExecutor background_executor;
BackgroundMovesExecutor background_moves_executor;
/// For block numbers.
SimpleIncrement increment;
/// For clearOldParts, clearOldTemporaryDirectories.
AtomicStopwatch time_after_previous_cleanup;
/// Mutex for parts currently processing in background
/// merging (also with TTL), mutating or moving.
mutable std::mutex currently_processing_in_background_mutex;
mutable std::condition_variable currently_processing_in_background_condition;
/// Parts that currently participate in merge or mutation.
/// This set have to be used with `currently_processing_in_background_mutex`.
DataParts currently_merging_mutating_parts;
std::map<String, MergeTreeMutationEntry> current_mutations_by_id;
std::multimap<Int64, MergeTreeMutationEntry &> current_mutations_by_version;
std::atomic<bool> shutdown_called {false};
void loadMutations();
/** Determines what parts should be merged and merges it.
* If aggressive - when selects parts don't takes into account their ratio size and novelty (used for OPTIMIZE query).
* Returns true if merge is finished successfully.
*/
bool merge(bool aggressive, const String & partition_id, bool final, bool deduplicate, const Names & deduplicate_by_columns, String * out_disable_reason = nullptr, bool optimize_skip_merged_partitions = false);
/// Make part state outdated and queue it to remove without timeout
/// If force, then stop merges and block them until part state became outdated. Throw exception if part doesn't exists
/// If not force, then take merges selector and check that part is not participating in background operations.
MergeTreeDataPartPtr outdatePart(const String & part_name, bool force);
ActionLock stopMergesAndWait();
/// Allocate block number for new mutation, write mutation to disk
/// and into in-memory structures. Wake up merge-mutation task.
Int64 startMutation(const MutationCommands & commands, String & mutation_file_name);
/// Wait until mutation with version will finish mutation for all parts
void waitForMutation(Int64 version, const String & file_name);
struct CurrentlyMergingPartsTagger
{
FutureMergedMutatedPart future_part;
ReservationPtr reserved_space;
StorageMergeTree & storage;
CurrentlyMergingPartsTagger(
FutureMergedMutatedPart & future_part_,
size_t total_size,
StorageMergeTree & storage_,
const StorageMetadataPtr & metadata_snapshot,
bool is_mutation);
~CurrentlyMergingPartsTagger();
};
using CurrentlyMergingPartsTaggerPtr = std::unique_ptr<CurrentlyMergingPartsTagger>;
friend struct CurrentlyMergingPartsTagger;
struct MergeMutateSelectedEntry
{
FutureMergedMutatedPart future_part;
CurrentlyMergingPartsTaggerPtr tagger;
MutationCommands commands;
MergeMutateSelectedEntry(const FutureMergedMutatedPart & future_part_, CurrentlyMergingPartsTaggerPtr && tagger_, const MutationCommands & commands_)
: future_part(future_part_)
, tagger(std::move(tagger_))
, commands(commands_)
{}
};
std::shared_ptr<MergeMutateSelectedEntry> selectPartsToMerge(
const StorageMetadataPtr & metadata_snapshot,
bool aggressive,
const String & partition_id,
bool final,
String * disable_reason,
TableLockHolder & table_lock_holder,
bool optimize_skip_merged_partitions = false,
SelectPartsDecision * select_decision_out = nullptr);
bool mergeSelectedParts(const StorageMetadataPtr & metadata_snapshot, bool deduplicate, const Names & deduplicate_by_columns, MergeMutateSelectedEntry & entry, TableLockHolder & table_lock_holder);
std::shared_ptr<MergeMutateSelectedEntry> selectPartsToMutate(const StorageMetadataPtr & metadata_snapshot, String * disable_reason, TableLockHolder & table_lock_holder);
bool mutateSelectedPart(const StorageMetadataPtr & metadata_snapshot, MergeMutateSelectedEntry & entry, TableLockHolder & table_lock_holder);
Int64 getCurrentMutationVersion(
const DataPartPtr & part,
std::unique_lock<std::mutex> & /* currently_processing_in_background_mutex_lock */) const;
void clearOldMutations(bool truncate = false);
// Partition helpers
void dropPartition(const ASTPtr & partition, bool detach, bool drop_part, const Context & context, bool throw_if_noop) override;
PartitionCommandsResultInfo attachPartition(const ASTPtr & partition, const StorageMetadataPtr & metadata_snapshot, bool part, const Context & context) override;
void replacePartitionFrom(const StoragePtr & source_table, const ASTPtr & partition, bool replace, const Context & context) override;
void movePartitionToTable(const StoragePtr & dest_table, const ASTPtr & partition, const Context & context) override;
bool partIsAssignedToBackgroundOperation(const DataPartPtr & part) const override;
/// Update mutation entries after part mutation execution. May reset old
/// errors if mutation was successful. Otherwise update last_failed* fields
/// in mutation entries.
void updateMutationEntriesErrors(FutureMergedMutatedPart result_part, bool is_successful, const String & exception_message);
/// Return empty optional if mutation was killed. Otherwise return partially
/// filled mutation status with information about error (latest_fail*) and
/// is_done. mutation_ids filled with mutations with the same errors,
/// because we can execute several mutations at once. Order is important for
/// better readability of exception message. If mutation was killed doesn't
/// return any ids.
std::optional<MergeTreeMutationStatus> getIncompleteMutationsStatus(Int64 mutation_version, std::set<String> * mutation_ids = nullptr) const;
void startBackgroundMovesIfNeeded() override;
friend class MergeTreeBlockOutputStream;
friend class MergeTreeData;
protected:
/** Attach the table with the appropriate name, along the appropriate path (with / at the end),
* (correctness of names and paths are not checked)
* consisting of the specified columns.
*
* See MergeTreeData constructor for comments on parameters.
*/
StorageMergeTree(
const StorageID & table_id_,
const String & relative_data_path_,
const StorageInMemoryMetadata & metadata,
bool attach,
Context & context_,
const String & date_column_name,
const MergingParams & merging_params_,
std::unique_ptr<MergeTreeSettings> settings_,
bool has_force_restore_data_flag);
MutationCommands getFirstAlterMutationCommandsForPart(const DataPartPtr & part) const override;
};
}