Characterizing the Influence of System Noise on Large-Scale Applications by Simulation
SESSION: Scalable System Software
EVENT TYPE: Paper, Best Paper (BP) Finalist
TIME: 4:30PM - 5:00PM
SESSION CHAIR: Franck Cappello
AUTHOR(S):Torsten Hoefler, Timo Schneider, Andrew Lumsdaine
ROOM:393
ABSTRACT: This paper presents an in-depth analysis of the impact of system noise on large-scale parallel
application performance in realistic settings. Our analytical model shows that not only collective operations but also point-to-point communications influence the application's sensitivity to noise. We present a simulation toolchain that injects noise delays from traces gathered on common large-scale architectures into a LogGPS simulation and allows new insights into the scaling of applications in noisy environments. We investigate collective operations with up to 1
million processes and three applications (Sweep3D, AMG, and POP) with up to 32,000 processes. We show that the scale at which noise becomes a bottleneck is system-specific and depends on the structure of the noise. Simulations with different network speeds show that a 10x faster network does not improve application scalability. We quantify noise and conclude that our tools can be utilized to tune the noise signatures of a specific system.
Chair/Author Details:
Franck Cappello (Chair) - INRIA and UIUC
Torsten Hoefler - University of Illinois at Urbana-Champaign
