COMPASS Talk by Ioannis Koltsidas (IBM Research Zurich): System software for commodity solid-state storage

22.02.2018 11:00


COMPASS: Computing Platforms Seminar Series

CAB E 72

Speaker : Ioannis Koltsidas (IBM Research Zurich)

System software for commodity solid-state storage






The high-performance storage landscape is being shaped by three main developments: a) Flash memories are scaling to extreme densities (e.g., 3D-TLC, QLC), b) new storage devices offer single-digit microsecond latencies (e.g., SSDs based on 3D-Xpoint memory), c) new standards provide high-performance, efficient access to local (e.g., NVMe) and remote storage (e.g., NVMeoF).

In this talk we present our work on building systems to maximize the benefits of new technologies, targeting commodity hardware environments such as cloud datacenters. Specifically, we focus on: a) Improving performance and endurance of low-cost Flash via a host translation layer, and b) exploiting low-latency NVM devices to reduce the cost and increase the scalability of systems that would otherwise rely on large amounts of DRAM.

Key ingredients in our stack include a storage virtualization layer, an efficient Key-Value storage engine built specifically for the new types of media, and a novel task-based I/O runtime system that enables CPU-efficient, high performance access to storage in a programmer-friendly way. We present an overview of these technologies along with lessons learned while building them, as well as experimental evidence that demonstrate their applicability.


Ioannis (Yannis) Koltsidas is a Research Staff Member in the Cloud Computing Infrastructure department at the IBM Research Lab in Zurich, Switzerland. In his current role he is leading a team of researchers doing research on next-generation Flash-enabled storage systems, exploitation of Flash memory in host servers, as well as applications of Storage-class Memories, such as Phase-Change Memory. His interests also include distributed scale-out file storage (GPFS, HDFS) and extensions thereof based on open-format magnetic tape. Some of the latest projects he has been involved in include the IBM FlashSystem, the IBM Easy Tier Server for the DS8000 series and the IBM LTFS Enterprise Edition.

Previously, Ioannis received his PhD in Computer Science from the University of Edinburgh, where he was a member of the Database Group at the School of Informatics. His research was supervised by Prof. Stratis Viglas. The focus of his thesis, titled "Flashing Up The Storage Hierarchy", was on database systems and data-intensive systems in general that employ novel storage media, such as NAND Flash SSDs and use novel algorithms and data structures to boost I/O performance. Prior to that, Ioannis completed his undergraduate studies at the Electrical and Computer Engineering Department of the National Techinical University of Athens (NTUA) in Athens, Greece, where he majored in Computer Science. =========