#pragma once #include #include #include namespace DB { class MergeTreeBlockOutputStream : public IBlockOutputStream { public: MergeTreeBlockOutputStream(StorageMergeTree & storage_) : storage(storage_) {} void writePrefix() override { /// If too much parts, do extra merges synchronously, in current thread. /// Why 10? - just in case, it is better than possibly infinite loop. for (size_t i = 0; i < 10; ++i) { size_t parts_count = storage.data.getMaxPartsCountForMonth(); if (parts_count <= storage.data.settings.parts_to_delay_insert) break; ProfileEvents::increment(ProfileEvents::SynchronousMergeOnInsert); storage.merge(0, {}, {}, {}, {}); } } void write(const Block & block) override { auto part_blocks = storage.writer.splitBlockIntoParts(block); for (auto & current_block : part_blocks) { Int64 temp_index = storage.increment.get(); MergeTreeData::MutableDataPartPtr part = storage.writer.writeTempPart(current_block, temp_index); storage.data.renameTempPartAndAdd(part, &storage.increment); /// Initiate async merge - it will be done if it's good time for merge and if there are space in 'background_pool'. storage.merge_task_handle->wake(); } } private: StorageMergeTree & storage; }; }