Main-memory DBMS can offer hybrid and evolving storage architectures, instead of the traditional row or column storage layouts. Even if RAM is affordable nowadays, it is still a limited resource concerning available storage space in comparison to conventional storage devices. Due to this space restriction, techniques that leverage a trade-off between storage and query performance were developed and should be applied to data that is not frequently accessed or updated. This work proposes SmartLTM, a data eviction mechanism that considers the decisions previously taken by the DBMS in optimizing data storage according to query workload. We discuss how to migrate data, access it and the main differences between our approach and a row-based one. We also analyze the behavior of our solution in different storage media. Experiments show that cold data access with SmartLTM incurs an acceptable 17% of throughput loss, against 26% of the row-based one, while retrieving only half of the data to answer queries.

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Unit tests are one of the most widely used tools to assure a minimal level of quality and compliance during development. However, they are not used in many projects where development takes place at low-level contexts. The main reason is that unit test development itself demands more time and becomes expensive in this context and tools that assist test creation are rare or absent. In UEFI development this scenario matches the reality of most teams and unit testing as well as other testing techniques are often not used. To address this fault we propose UTTOS, a tool that parses EDKII build configuration files, mocks the UEFI-specific functions for C development and enables UEFI test suite code to run in the operating system. We show that UTTOS is able to run the test suit in the operating system and save development time.