Performability Aspects of the Atlas Vo; Using Lmbench Suite

TL;DR

This paper evaluates the performability of the ATLAS Virtual Organization's heterogeneous grid systems using the LMbench suite, highlighting the limitations of current performance assessment methods and the need for new resource allocation techniques.

Contribution

It demonstrates the significant heterogeneity in grid system performance and critiques existing evaluation practices, proposing the necessity for improved techniques for resource management.

Findings

Performance spread does not follow known distributions.

Current evaluation practices are oversimplified and costly.

Heterogeneity impacts resource allocation strategies.

Abstract

The ATLAS Virtual Organization is grid's largest Virtual Organization which is currently in full production stage. Hereby a case is being made that a user working within that VO is going to face a wide spectrum of different systems, whose heterogeneity is enough to count as "orders of magnitude" according to a number of metrics; including integer/float operations, memory throughput (STREAM) and communication latencies. Furthermore, the spread of performance does not appear to follow any known distribution pattern, which is demonstrated in graphs produced during May 2007 measurements. It is implied that the current practice where either "all-WNs-are-equal" or, the alternative of SPEC-based rating used by LCG/EGEE is an oversimplification which is inappropriate and expensive from an operational point of view, therefore new techniques are needed for optimal grid resources allocation.