New capabilities in the HENP Grand Challenge Storage Access System and itsapplication at RHIC

Citation
L. Bernardo et al., New capabilities in the HENP Grand Challenge Storage Access System and itsapplication at RHIC, COMP PHYS C, 140(1-2), 2001, pp. 179-188
Citations number
5
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Physics
Journal title
COMPUTER PHYSICS COMMUNICATIONS
ISSN journal
0010-4655 → ACNP
Volume
140
Issue
1-2
Year of publication
2001
Pages
179 - 188
Database
ISI
SICI code
0010-4655(20011015)140:1-2<179:NCITHG>2.0.ZU;2-R
Abstract
The High Energy and Nuclear Physics Data Access Grand Challenge project has developed an optimizing storage access software system that was prototyped at RHIC. It is currently undergoing integration with the STAR experiment i n preparation for data taking that starts in mid-2000. The behavior and les sons learned in the RHIC Mock Data Challenge exercises are described as wel l as the observed performance under conditions designed to characterize sca lability. Up to 250 simultaneous queries were tested and up to 10 million e vents across 7 event components were involved in these queries. The system coordinates the staging of "bundles" of files from the HPSS tape system, so that all the needed components of each event are in disk cache when access ed by the application software. The caching policy algorithm for the coordi nated bundle staging is described in the paper. The initial prototype imple mentation interfaced to the Objectivity/DB. In this latest version, it evol ved to work with arbitrary files and use CORBA interfaces to the tag databa se and file catalog services. The interface to the tag database and the MyS QL-based file catalog services used by STAR are described along with the pl anned usage scenarios. (C) 2001 Elsevier Science B.V. All rights reserved.