#pragma once #include #include #include #include namespace DB { /** Merge selector, which is used to remove values with expired ttl. * It selects parts to merge by greedy algorithm: * 1. Finds part with the most earliest expired ttl and includes it to result. * 2. Tries to find the longest range of parts with expired ttl, that includes part from step 1. * Finally, merge selector updates TTL merge timer for the selected partition */ class ITTLMergeSelector : public IMergeSelector { public: using PartitionIdToTTLs = std::map; ITTLMergeSelector(PartitionIdToTTLs & merge_due_times_, time_t current_time_, Int64 merge_cooldown_time_, bool dry_run_) : current_time(current_time_) , merge_due_times(merge_due_times_) , merge_cooldown_time(merge_cooldown_time_) , dry_run(dry_run_) { } PartsRange select( const PartsRanges & parts_ranges, size_t max_total_size_to_merge) override; /// Get TTL value for part, may depend on child type and some settings in /// constructor. virtual time_t getTTLForPart(const IMergeSelector::Part & part) const = 0; /// Sometimes we can check that TTL already satisfied using information /// stored in part and don't assign merge for such part. virtual bool isTTLAlreadySatisfied(const IMergeSelector::Part & part) const = 0; protected: time_t current_time; private: PartitionIdToTTLs & merge_due_times; Int64 merge_cooldown_time; bool dry_run; }; /// Select parts to merge using information about delete TTL. Depending on flag /// only_drop_parts can use max or min TTL value. class TTLDeleteMergeSelector : public ITTLMergeSelector { public: using PartitionIdToTTLs = std::map; TTLDeleteMergeSelector(PartitionIdToTTLs & merge_due_times_, time_t current_time_, Int64 merge_cooldown_time_, bool only_drop_parts_, bool dry_run_) : ITTLMergeSelector(merge_due_times_, current_time_, merge_cooldown_time_, dry_run_) , only_drop_parts(only_drop_parts_) {} time_t getTTLForPart(const IMergeSelector::Part & part) const override; /// Delete TTL should be checked only by TTL time, there are no other ways /// to satisfy it. bool isTTLAlreadySatisfied(const IMergeSelector::Part &) const override; private: bool only_drop_parts; }; /// Select parts to merge using information about recompression TTL and /// compression codec of existing parts. class TTLRecompressMergeSelector : public ITTLMergeSelector { public: TTLRecompressMergeSelector(PartitionIdToTTLs & merge_due_times_, time_t current_time_, Int64 merge_cooldown_time_, const TTLDescriptions & recompression_ttls_, bool dry_run_) : ITTLMergeSelector(merge_due_times_, current_time_, merge_cooldown_time_, dry_run_) , recompression_ttls(recompression_ttls_) {} /// Return part min recompression TTL. time_t getTTLForPart(const IMergeSelector::Part & part) const override; /// Checks that part's codec is not already equal to required codec /// according to recompression TTL. It doesn't make sense to assign such /// merge. bool isTTLAlreadySatisfied(const IMergeSelector::Part & part) const override; private: TTLDescriptions recompression_ttls; }; }