Abstract-It has become increasingly important to capture and understand the origins and derivation of data (its provenance). A key issue in evaluating the feasibility of data provenance is its performance, overheads, and scalability. In this paper, we explore the feasibility of a general metadata storage and management layer for parallel file systems, in which metadata includes both file operations and provenance metadata. We experimentally investigate the design optimality-whether provenance metadata should be loosely-coupled or tightly integrated with a file metadata storage systems. We consider two systems that have applied similar distributed concepts to metadata management, but focusing singularly on kind of metadata: (i) FusionFS, which implements a distributed file metadata management based on distributed hash tables, and (ii) SPADE, which uses a graph database to store audited provenance data and provides distributed module for querying provenance. Our results on a 32-node cluster show that FusionFS+SPADE is a promising prototype with negligible provenance overhead and has promise to scale to petascale and beyond. Furthermore, FusionFS with its own storage layer for provenance capture is able to scale up to 1K nodes on BlueGene/P supercomputer.

Background Measles is an infectious disease caused by the Morbillivirus. Chinese physicians believe that medicinal herbs are e ective in alleviating symptoms and preventing complications. Chinese herbal medicines are dispensed according to the particular symptoms. This is the second update of a Cochrane Review first published in 2006. Objectives To assess the e ectiveness and possible adverse e ects of Chinese medicinal herbs for measles.