Link to the University of Pittsburgh Homepage
Link to the University Library System Homepage Link to the Contact Us Form

Secure, Reliable, and Energy-efficient Phase Change Main Memory

Longofono, Stephen Joseph (2021) Secure, Reliable, and Energy-efficient Phase Change Main Memory. Master's Thesis, University of Pittsburgh. (Unpublished)

PDF (Final Version)
Download (3MB) | Preview


Recent trends in supercomputing, shared cloud computing, and “big data” applications are placing ever-greater demands on computing systems and their memories. Such applications can readily saturate memory bandwidth, and often operate on a working set which exceeds the capacity of modern DRAM packages. Unfortunately, this demand is not matched by DRAM technology development. As Moore’s Law slows and Dennard Scaling stops, further density improvements in DRAM and the underlying semiconductor devices are difficult [1]. In anticipation of this limitation, researchers have pursued emerging memory technologies that promise higher density than conventional DRAM devices. One such technology in phase-change memory (PCM) is especially desirable due to its increased density relative to DRAM. However, this nascent memory has outstanding challenges to overcome before it is viable as a DRAM replacement. PCM devices have limited write endurance, and can consume more energy than their DRAM counterparts, necessitating careful control of how and how often they are written. A second challenge is the non-volatile nature of PCM devices; many applications rely on the volatility of DRAM to protect security critical applications and operating system address space between accesses and power cycles. An obvious solution is to encrypt the memory, but the effective randomization of data is at odds with techniques which reduce writes to the underlying memory. This body of work presents three contributions for addressing all challenges simultaneously under the assumption that encryption is required. Using an encryption and encoding technique called CASTLE & TOWERs, PCM can be employed as main memory with up to 30× improvement in device lifetime while opportunistically reducing dynamic energy. A second technique called MACE marries encoding and traditional error-correction schemes providing up to 2.6× improvement in device lifetime alongside a whole-lifetime energy evaluation framework to guide system design. Finally, an architecture called WINDU is presented which supports the application of encoding for an emerging encryption standard with an eye on energy efficiency. Together, these techniques advance the state-of-the-art, and offer a significant step toward the adoption of PCM as a main memory.


Social Networking:
Share |


Item Type: University of Pittsburgh ETD
Status: Unpublished
CreatorsEmailPitt UsernameORCID
Longofono, Stephen Josephstl77@pitt.edustl770000-0002-5237-8705
ETD Committee:
TitleMemberEmail AddressPitt UsernameORCID
Thesis AdvisorJones, Alexakjones@pitt.eduakjones0000-0001-7498-0206
Committee ChairJones, Alexakjones@pitt.eduakjones0000-0001-7498-0206
Committee MemberHu, Jingtongjthu@pitt.edujthu0000-0003-4029-4034
Committee MemberXiong, Fengf.xiong@pitt.edufex140000-0001-8383-5182
Date: 3 September 2021
Date Type: Publication
Defense Date: 1 July 2021
Approval Date: 3 September 2021
Submission Date: 10 June 2021
Access Restriction: No restriction; Release the ETD for access worldwide immediately.
Number of Pages: 75
Institution: University of Pittsburgh
Schools and Programs: Swanson School of Engineering > Electrical and Computer Engineering
Degree: MS - Master of Science
Thesis Type: Master's Thesis
Refereed: Yes
Uncontrolled Keywords: emerging memory technology, phase change memory, fault tolerance, sustainability
Date Deposited: 03 Sep 2021 15:39
Last Modified: 03 Sep 2021 15:39


Monthly Views for the past 3 years

Plum Analytics

Actions (login required)

View Item View Item