For some reasons when we delete a MergeTree Part in atomic way something may go wrong - and leave the `delete_tmp_*` folder or it's part on disk. This may lead to a disk space consumption over time.

It's suggested to delete this folders at least at server start-up. Current solution with `clearOldTemporaryDirectories()` doesn't work because this method is called periodically from a thread without any locks or advisory on folders - it may cause the race conditions.
bool supportsFinal() const override;
    bool supportsSubcolumns() const override { return true; }
    bool supportsTTL() const override { return true; }
    bool supportsDynamicSubcolumns() const override { return true; }
    NamesAndTypesList getVirtuals() const override;
    bool mayBenefitFromIndexForIn(const ASTPtr & left_in_operand, ContextPtr, const StorageMetadataPtr & metadata_snapshot) const override;
    
    
    struct SnapshotData : public StorageSnapshot::Data
    {
        DataPartsVector parts;
    };
    StorageSnapshotPtr getStorageSnapshot(const StorageMetadataPtr & metadata_snapshot, ContextPtr query_context) const override;
    
    void loadDataParts(bool skip_sanity_checks);
    String getLogName() const { return log_name; }