Get rid of background processing pool

src/Interpreters/Context.cpp

@@ -18,7 +18,6 @@
 #include <Databases/IDatabase.h>
 #include <Storages/IStorage.h>
 #include <Storages/MarkCache.h>
-#include <Storages/MergeTree/BackgroundProcessingPool.h>
 #include <Storages/MergeTree/MergeList.h>
 #include <Storages/MergeTree/MergeTreeSettings.h>
 #include <Storages/CompressionCodecSelector.h>
@@ -331,8 +330,6 @@ struct ContextShared
     ConfigurationPtr users_config;                          /// Config with the users, profiles and quotas sections.
     InterserverIOHandler interserver_io_handler;            /// Handler for interserver communication.
     std::optional<BackgroundSchedulePool> buffer_flush_schedule_pool; /// A thread pool that can do background flush for Buffer tables.
-    std::optional<BackgroundProcessingPool> background_pool; /// The thread pool for the background work performed by the tables.
-    std::optional<BackgroundProcessingPool> background_move_pool; /// The thread pool for the background moves performed by the tables.
     std::optional<BackgroundSchedulePool> schedule_pool;    /// A thread pool that can run different jobs in background (used in replicated tables)
     std::optional<BackgroundSchedulePool> distributed_schedule_pool; /// A thread pool that can run different jobs in background (used for distributed sends)
     std::optional<BackgroundSchedulePool> message_broker_schedule_pool;    /// A thread pool that can run different jobs in background (used in kafka streaming)
@@ -433,8 +430,6 @@ struct ContextShared
         external_dictionaries_loader.reset();
         external_models_loader.reset();
         buffer_flush_schedule_pool.reset();
-        background_pool.reset();
-        background_move_pool.reset();
         schedule_pool.reset();
         distributed_schedule_pool.reset();
         ddl_worker.reset();
@@ -1369,45 +1364,6 @@ void Context::dropCaches() const
         shared->mark_cache->reset();
 }
 
-BackgroundProcessingPool & Context::getBackgroundPool()
-{
-    auto lock = getLock();
-    if (!shared->background_pool)
-    {
-        BackgroundProcessingPool::PoolSettings pool_settings;
-        const auto & config = getConfigRef();
-        pool_settings.thread_sleep_seconds = config.getDouble("background_processing_pool_thread_sleep_seconds", 10);
-        pool_settings.thread_sleep_seconds_random_part = config.getDouble("background_processing_pool_thread_sleep_seconds_random_part", 1.0);
-        pool_settings.thread_sleep_seconds_if_nothing_to_do = config.getDouble("background_processing_pool_thread_sleep_seconds_if_nothing_to_do", 0.1);
-        pool_settings.task_sleep_seconds_when_no_work_min = config.getDouble("background_processing_pool_task_sleep_seconds_when_no_work_min", 10);
-        pool_settings.task_sleep_seconds_when_no_work_max = config.getDouble("background_processing_pool_task_sleep_seconds_when_no_work_max", 600);
-        pool_settings.task_sleep_seconds_when_no_work_multiplier = config.getDouble("background_processing_pool_task_sleep_seconds_when_no_work_multiplier", 1.1);
-        pool_settings.task_sleep_seconds_when_no_work_random_part = config.getDouble("background_processing_pool_task_sleep_seconds_when_no_work_random_part", 1.0);
-        shared->background_pool.emplace(settings.background_pool_size, pool_settings);
-    }
-    return *shared->background_pool;
-}
-
-BackgroundProcessingPool & Context::getBackgroundMovePool()
-{
-    auto lock = getLock();
-    if (!shared->background_move_pool)
-    {
-        BackgroundProcessingPool::PoolSettings pool_settings;
-        const auto & config = getConfigRef();
-        pool_settings.thread_sleep_seconds = config.getDouble("background_move_processing_pool_thread_sleep_seconds", 10);
-        pool_settings.thread_sleep_seconds_random_part = config.getDouble("background_move_processing_pool_thread_sleep_seconds_random_part", 1.0);
-        pool_settings.thread_sleep_seconds_if_nothing_to_do = config.getDouble("background_move_processing_pool_thread_sleep_seconds_if_nothing_to_do", 0.1);
-        pool_settings.task_sleep_seconds_when_no_work_min = config.getDouble("background_move_processing_pool_task_sleep_seconds_when_no_work_min", 10);
-        pool_settings.task_sleep_seconds_when_no_work_max = config.getDouble("background_move_processing_pool_task_sleep_seconds_when_no_work_max", 600);
-        pool_settings.task_sleep_seconds_when_no_work_multiplier = config.getDouble("background_move_processing_pool_task_sleep_seconds_when_no_work_multiplier", 1.1);
-        pool_settings.task_sleep_seconds_when_no_work_random_part = config.getDouble("background_move_processing_pool_task_sleep_seconds_when_no_work_random_part", 1.0);
-        pool_settings.tasks_metric = CurrentMetrics::BackgroundMovePoolTask;
-        shared->background_move_pool.emplace(settings.background_move_pool_size, pool_settings, "BackgroundMovePool", "BgMoveProcPool");
-    }
-    return *shared->background_move_pool;
-}
-
 BackgroundSchedulePool & Context::getBufferFlushSchedulePool()
 {
     auto lock = getLock();

src/Interpreters/Context.h

@@ -62,7 +62,6 @@ class EmbeddedDictionaries;
 class ExternalDictionariesLoader;
 class ExternalModelsLoader;
 class InterserverIOHandler;
-class BackgroundProcessingPool;
 class BackgroundSchedulePool;
 class MergeList;
 class Cluster;
@@ -508,8 +507,6 @@ public:
     void dropCaches() const;
 
     BackgroundSchedulePool & getBufferFlushSchedulePool();
-    BackgroundProcessingPool & getBackgroundPool();
-    BackgroundProcessingPool & getBackgroundMovePool();
     BackgroundSchedulePool & getSchedulePool();
     BackgroundSchedulePool & getMessageBrokerSchedulePool();
     BackgroundSchedulePool & getDistributedSchedulePool();

src/Storages/MergeTree/BackgroundJobsExecutor.h

@@ -3,11 +3,38 @@
 #include <Storages/MergeTree/MergeTreeData.h>
 #include <Common/ThreadPool.h>
 #include <Core/BackgroundSchedulePool.h>
-#include <Storages/MergeTree/BackgroundProcessingPool.h>
 #include <pcg_random.hpp>
 
+namespace CurrentMetrics
+{
+    extern const Metric BackgroundPoolTask;
+}
+
 namespace DB
 {
+enum PoolType
+{
+    MERGE_MUTATING,
+    MOVING,
+
+}
+
+struct PoolSettings
+{
+    double thread_sleep_seconds = 10;
+    double thread_sleep_seconds_random_part = 1.0;
+    double thread_sleep_seconds_if_nothing_to_do = 0.1;
+
+    /// For exponential backoff.
+    double task_sleep_seconds_when_no_work_min = 10;
+    double task_sleep_seconds_when_no_work_max = 600;
+    double task_sleep_seconds_when_no_work_multiplier = 1.1;
+    double task_sleep_seconds_when_no_work_random_part = 1.0;
+
+    CurrentMetrics::Metric tasks_metric = CurrentMetrics::BackgroundPoolTask;
+
+    PoolSettings() noexcept {}
+};
 
 class BackgroundJobsExecutor
 {
@@ -19,7 +46,7 @@ private:
     ThreadPool move_pool;
     std::atomic<size_t> errors_count{0};
     pcg64 rng;
-    BackgroundProcessingPool::PoolSettings settings;
+    PoolSettings settings;
 
     BackgroundSchedulePool::TaskHolder data_processing_task;
     BackgroundSchedulePool::TaskHolder data_moving_task;

src/Storages/StorageMergeTree.cpp

@@ -762,23 +762,6 @@ bool StorageMergeTree::partIsAssignedToBackgroundOperation(const DataPartPtr & p
     return currently_merging_mutating_parts.count(part);
 }
 
-
-BackgroundProcessingPoolTaskResult StorageMergeTree::movePartsTask()
-{
-    try
-    {
-        if (!selectPartsAndMove())
-            return BackgroundProcessingPoolTaskResult::NOTHING_TO_DO;
-
-        return BackgroundProcessingPoolTaskResult::SUCCESS;
-    }
-    catch (...)
-    {
-        tryLogCurrentException(log);
-        return BackgroundProcessingPoolTaskResult::ERROR;
-    }
-}
-
 std::optional<StorageMergeTree::MergeMutateSelectedEntry> StorageMergeTree::selectPartsToMutate(const StorageMetadataPtr & metadata_snapshot, String */* disable_reason */)
 {
     auto table_lock_holder = lockForShare(RWLockImpl::NO_QUERY, getSettings()->lock_acquire_timeout_for_background_operations);

src/Storages/StorageMergeTree.h

@@ -13,7 +13,6 @@
 #include <Storages/MergeTree/MergeTreeMutationEntry.h>
 #include <Storages/MergeTree/MergeTreeMutationStatus.h>
 #include <Disks/StoragePolicy.h>
-#include <Storages/MergeTree/BackgroundProcessingPool.h>
 #include <Common/SimpleIncrement.h>
 #include <Core/BackgroundSchedulePool.h>
 #include <Storages/MergeTree/BackgroundJobsExecutor.h>
@@ -131,8 +130,6 @@ private:
 
     ActionLock stopMergesAndWait();
 
-    BackgroundProcessingPoolTaskResult movePartsTask();
-
     /// 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);

src/Storages/StorageReplicatedMergeTree.cpp

@@ -2626,23 +2626,6 @@ bool StorageReplicatedMergeTree::partIsAssignedToBackgroundOperation(const DataP
     return queue.isVirtualPart(part);
 }
 
-BackgroundProcessingPoolTaskResult StorageReplicatedMergeTree::movePartsTask()
-{
-    try
-    {
-        if (!selectPartsAndMove())
-            return BackgroundProcessingPoolTaskResult::NOTHING_TO_DO;
-
-        return BackgroundProcessingPoolTaskResult::SUCCESS;
-    }
-    catch (...)
-    {
-        tryLogCurrentException(log);
-        return BackgroundProcessingPoolTaskResult::ERROR;
-    }
-}
-
-
 void StorageReplicatedMergeTree::mergeSelectingTask()
 {
     if (!is_leader)

src/Storages/StorageReplicatedMergeTree.h

@@ -16,7 +16,6 @@
 #include <Storages/MergeTree/ReplicatedMergeTreePartCheckThread.h>
 #include <Storages/MergeTree/ReplicatedMergeTreeTableMetadata.h>
 #include <Storages/MergeTree/EphemeralLockInZooKeeper.h>
-#include <Storages/MergeTree/BackgroundProcessingPool.h>
 #include <Storages/MergeTree/DataPartsExchange.h>
 #include <Storages/MergeTree/ReplicatedMergeTreeAddress.h>
 #include <Storages/MergeTree/LeaderElection.h>
@@ -284,10 +283,6 @@ private:
 
     BackgroundSchedulePool::TaskHolder mutations_updating_task;
 
-    /// A task which move parts to another disks/volumes
-    /// Transparent for replication.
-    BackgroundProcessingPool::TaskHandle move_parts_task_handle;
-
     /// A task that selects parts to merge.
     BackgroundSchedulePool::TaskHolder merge_selecting_task;
     /// It is acquired for each iteration of the selection of parts to merge or each OPTIMIZE query.
@@ -423,10 +418,6 @@ private:
 
     bool processQueueEntry(ReplicatedMergeTreeQueue::SelectedEntry & entry);
 
-    /// Perform moves of parts to another disks.
-    /// Local operation, doesn't interact with replicationg queue.
-    BackgroundProcessingPoolTaskResult movePartsTask();
-
     /// Postcondition:
     /// either leader_election is fully initialized (node in ZK is created and the watching thread is launched)
     /// or an exception is thrown and leader_election is destroyed.