Experience with using CORBA to implement a file caching coordination system

Abstract

AbstractWe describe our experience with using several CORBA products to interconnect the software modules of a fairly complex system for file caching coordination from a tertiary storage. The application area that the system was designed for is High Energy and Nuclear Physics (HENP). In this application area, the volume of data reaches hundreds of terabytes per year and therefore it is impractical to store them on disk systems. Rather the data are organized into large files and stored on robotic tape systems that are managed by some Mass Storage System (MSS). The role of the Storage Access Coordination System (STACS) that we developed is to manage the caching of files from the MSS to a large disk cache that is shared by multiple HENP analysis programs. The system design involved multiple components developed by different people at different sites and the modules could potentially be distributed as well. In this paper we describe the architecture and implementation of STACS, emphasizing the inter‐module communication requirements. We describe the use of CORBA interfaces between system components, and our experience with using multi‐threaded CORBA and using hundreds of concurrent CORBA connections. STACS development was recently completed and is being incorporated in an operational environment that started to produce data in the summer of 2000 [1]. Copyright © 2001 John Wiley & Sons, Ltd.