Computing Platforms Seminar Series (COMPASS)

The Computing Platforms Seminar Series (COMPASS) is focused on talks by industry and academia around the general topic of computing platforms.

COMPASS is held on most Thursdays during the semester 10:00-11:00 (with some exceptions) in CAB E 72.

Upcoming Talks:


Thursday, 25 October 2018, 10:00-11:00 in CAB E 72

Speaker: Mihnea Andrei (SAP HANA)

Title: Snapshot isolation in HANA - the evolution towards production-grade HTAP


Pioneered by SAP HANA, Hybrid Transactional Analytical Processing (HTAP) has become today an industry trend, adopted by most major database vendors. In the past, Online Transactional Processing (OLTP) and Online Analytical Processing (OLAP) were executed separately, on dedicated systems, each optimized for the respective workload. Initially, the optimizations pertained more to the logical and physical data models; but later specialized database engines emerged, as row vs. column stores, native cubes, etc. Despite the performance advantage of this "one side does not fit all" approach, it has the practical disadvantage of putting on the user to absorb the complexity of operating two different systems, and their data movement. This involves many moving parts, each prone to failure, with subtle difference in the semantics of the data models and processing. Conversely, HTAP systems absorb this complexity and offer both of OLTP and OLAP processing within the same system, with the same transaction domain guarantees, on the same data set, and with excellent performance. HTAP was made possible through in-memory computing, itself based by new software technology leveraging modern hardware, as very large DRAM capacity, large number of processing cores, etc. - and more recently NVRAM.

In this talk, I start with an introduction to the internals of HANA, covering both the concept of HTAP and the underlying technologies used in HANA to enable it within a single system. The second part of the talk focuses on HANA's productive implementation of snapshot isolation. After a refresh on transactional consistency principles and techniques, I present HANA’s original OLAP oriented implementation. The main part of the talk coverts the implementation's evolution to the current version, which enables HTAP. I conclude with a post-mortem analysis of the good and bad, and give an outlook to future work.


Mihnea is a Chief Architect at SAP, working on the HANA database system. He covers a broad area, spanning core database technologies: in-memory, NVRAM, and on-disk stores; transaction processing; query optimization and execution, FPGA; distributed processing and RDMA, federation; and, more recently, DBaaS. His industry focus on databases started in 1993, when he joined Sybase, a Bay Area database editor. Mihnea worked on both of the state-of-the-art row oriented and column oriented Sybase database systems, which covered separately OLTP and OLAP workloads. Prior, he completed his DEA in Machine Learning in 1990, at the Université Paris 6, supervised by Prof. Jean-Gabriel Ganascia; and his MSc in Computer Science in 1988, at the Bucharest Polytechnic Institute.



Past COMPASS Talks:  

Date Speaker Affiliation Talk
04.10.2018 Philippe Bonnet IT University, Copenhagen, Denmark Near-Data Processing with Open-Channel SSDs
25.09.2018 Nandita Vijaykumar   Carnegie Mellon University Expressive Memory: Rethinking the Hardware-Software Contract with Rich Cross-Layer Abstractions
20.09.2018 Patrick Stüdi IBM Research Data processing at the speed of 100 Gbps using Apache Crail (Incubating)
15.08.2018 Leonid Yavits
Technion Resistive CAM based architectures: Resistive Associative In-Storage Processor and Resistive Address Decoder
06.07.2018 Martin Burtscher Texas State University Automatic Hierarchical Parallelization of Linear Recurrences
15.06.2018 Nitin Agrawal Samsung Research Low-Latency Analytics on Colossal Data Streams with SummaryStore
24.05.2018 Cagri Balkesen Oracle Labs RAPID: In-Memory Analytical Query Processing Engine with Extreme Performance per Watt
16.05.2018 Carsten Binnig TU Darmstadt Towards Interactive Data Exploration
09.05.2018 Bastian Hossbach Oracle Labs Modern programming languages and code generation in the Oracle Database
26.04.2018 Spyros Blanas Ohio State University Scaling database systems to high-performance computers
19.04.2018 Jane Hung MIT The Challenges and Promises of Large-Scale Biological Imaging
12.04.2018 Christoph Hagleitner IBM Research Heterogeneous Computing Systems for Datacenter and HPC Applications
14.03.2018  Eric Sedlar
 Oracle Labs
Why Systems Research Needs Social Science Added to the Computer Science
01.03.2018 Saughata Ghose Carnegie Mellon University How Safe Is Your Storage? A Look at the Reliability and Vulnerability of Modern Solid-State Drives
22.02.2018  Ioannis Koltsidas IBM Research Zurich System software for commodity solid-state storage