ECE Seminar: Mandelbugs In Database-Centric Applications
Monday, July 29, 2013 - 10:30am to 12:00pm
Mark Grechanik, Ph.D., Assistant Professor, Department of Computer Science, The University of Illinois at Chicago
TITLE: Mandelbugs In Database-Centric Applications Many organizations deploy applications that use databases by sending Structured Query Language(SQL) statements to them and obtaining data that result from the execution of these statements. Using database-centric applications introduces a new class of mandelbugs. In this talk we give examples of different mandelbugs for database-centric applications, and we concentrate on a specific mandelbug called database deadlock. Since applications often share the same databases concurrently, database deadlocks routinely occur in these databases resulting in major performance degradation in these applications. We created a novel approach which detects hold-and-wait cycles that specify how resources (e.g., database tables) are held in contention during executions of SQL statements. We rigorously evaluated our approach. For a realistic case of over 1,200 SQL statements, our algorithm detects all hold-and-wait cycles in less than two seconds. We built a toolset and experimented with three applications. Our tool prevented all existing database deadlocks in these applications and increased their throughputs by up to three orders of magnitude. BIO: Dr. Grechanik is an Assistant Professor at the Department of Computer Science of the University of Illinois at Chicago. Dr.Grechanik earned his Ph.D. in Computer Science from the department of Computer Sciences of the University of Texas at Austin.