11/22/2021
By William Moloney

The Kennedy College of Sciences, Department of Computer Science, invites you to the doctoral dissertation defense of Pavel Tatashin on "Provisioning of Cloud Systems with Minimal Tenant Disruption."

Ph.D. Candidate: Pavel Tatashin
Time: Monday, Dec. 6, 2021, 2 p.m.
Location: This will be a virtual defense via Zoom

Committee Members:

  • Thesis Supervisor: William Moloney, Associate Professor, Computer Science Department, University of Massachusetts Lowell
  • Jay McCarthy, Associate Professor, Computer Science Department, University of Massachusetts Lowell
  • Tom Wilkes, Assistant Teaching Professor, Computer Science Department, University of Massachusetts Lowell
  • Steve Sistare, Software Architect, Oracle Corporation

Abstract:

Cloud vendors provide slices of systems called virtual machines to tenants, with various guarantees of availability, performance, and stability. The stability and performance guarantees require the software stack and physical hardware to be kept updated, while the availability guarantee prohibits long downtimes. Thus, the vendors face the challenge of being able to perform software and hardware provisioning on their systems that is minimally disruptive to tenants.

This work encompasses an analysis and discussion of various techniques that can be used in order to allow cloud vendors to maintain stable and updated server farms with minimal or possibly no downtime or slowdowns of the virtual machines that they are hosting. The methods that are tested are quantified based on downtimes and slowdowns from the tenant's point of view when the underlying host software or hardware are being updated.

In addition, in this work we design and describe a reference virtualization appliance software stack that we use to analyze cloud hardware. The reference software stack is an image that is composed of a Linux kernel, a virtual machine manager and libraries. The total image size is small, under 20MiB, but has the necessary capabilities to handle real cloud work.