Novità alla Facoltà di scienze informatiche

Speaker: Raja Appuswamy
  EPFL, Switzerland
Date: Wednesday, October 11, 2017
Place: USI Lugano Campus, room A11, Red building (Via G. Buffi 13)
Time: 13:30-14:30



In 1987, Jim Gray and Gianfranco Putzolu introduced the five-minute rule for trading memory to reduce disk I/O using the then-current price-performance characteristics of DRAM and Hard Disk Drives (HDD). Since then, the five-minute rule has gained wide-spread acceptance as an important rule-of-thumb in data engineering. In the first part of this talk, we will revisit the five-minute rule three decades since its introduction and use it to identify impending changes in today's multi-tier storage hierarchy given recent trends in the storage hardware landscape.

In the second part of the talk, we will use insights from the five-minute rule to investigate the impact of merging the erstwhile-separate capacity and archival tiers into a single cold storage tier that is based on new Cold Storage Devices (CSD). We will see that despite its ability to reduce TCO, cold storage tier cannot be realized in practice today as current database systems will suffer from crippling performance problems if CSD are used as a replacement for HDD. Then, I will present Skipper, an end-to-end query execution framework that substantially reduces the cost of data analytics by enabling query execution directly over CSD.



Raja Appuswamy is currently working as a Postdoctoral Researcher in the DIAS lab headed by Prof. Anastasia Ailamaki at EPFL.  Previously, he worked as a Visiting Researcher in the Systems and Networking group at Microsoft Research, Cambridge, and as a Software Development Engineer in the Windows 7 kernel team at Microsoft, Redmond.

He received his PhD in Computer Science from the Vrije Universiteit, Amsterdam, where he worked under the guidance of Prof. Andrew S. Tanenbaum on designing and implementing a new storage stack for the MINIX 3 microkernel operating system. He also holds dual Masters degrees in Computer Science and Agricultural Engineering from the University of Florida.


Host: Prof. Fernando Pedone