80 likes | 167 Views
History. Test system HPSS 3.2 installation in Oct 1997 IBM AIX machines with IBM 3590 drives Port of mover to Digital Unix then started mostly functionality testing, no unexpected problems/delays API - simple & slow, or complex & fast sequential, needs application changes
E N D
History • Test system HPSS 3.2 installation in Oct 1997 • IBM AIX machines with IBM 3590 drives • Port of mover to Digital Unix then started • mostly functionality testing, no unexpected problems/delays • API - simple & slow, or complex & fast sequential, needs application changes • Modified existing CERN RFIO interface to use fast HPSS interface to profit from existing investment • Services started August 98 using HPSS 3.2 HPSS User Forum, Santa Fe CERN IT/PDP
CERN files - where do they go? • AFS: small files up to 20MB • home directories and some project files • HPSS: medium sized files > 20 MB, < 10 GB • used to be on user-managed tapes! • rfcp local-file hpsssrv1:/hpss/cern.ch/user/l/loginid/hpss-file • stagein -M /hpss/cern.ch/user/l/login/hpss-file link-file • hsm -x get /hpss/cern.ch/user/l/login/hpss-file local-file • “Transparent” to Objectivity DB users using modified SLAC AMS/HPSS interface • HPSS: Data taking for some experiments and test beams • performance and reliability are very important • files often go into the wrong COS HPSS User Forum, Santa Fe CERN IT/PDP
Production hardware HPSS 3.2 • IBM F50 RS/6000 main server (ns, bfs, etc.) • 512 MB RAM, 2 cpus, AIX 4.2.1.0 • Fastethernet • 2 IBM F50 RS/6000, disk & tape server • 256 MB RAM, 2 cpus, AIX 4.2.1.0 • 2 IBM 3590 drives, 10 GB cartridges • 4 x 7 x 18 GB disks mirrored • 344 GB total space in HPSS storage class 1 • 114 GB total space in HPSS storage class 4 (2 tape copies) • HIPPI & Gigabit • 2 COMPAQ Alpha 4100, disk & tape server • 512 MB RAM, 4 cpus, Digital unix 4.0D • 2 STK Redwood drives, 10GB, 25GB, 50B cartridges • 2 x 7 x 18 GB disks mirrored • 240 GB total space in HPSS storage class 2 • HIPPI & Gigabit HPSS User Forum, Santa Fe CERN IT/PDP
HPSS1D01 IBM RS/6000 F50 HPSS disk & tape Mover HPSS1D02 IBM RS/6000 F50 HPSS disk & tape Mover Hippi Gigabit Hippi Gigabit HPSSSRV1 Client Fast Ethernet Fast Ethernet IBM RS/6000 F50 Any Platform Network Hippi Chorus, NA57, etc... HPSS server Gigabit Gigabit Gigabit Hippi Hippi SHD55 SHD56 DEC AlphaServer 4100 DEC AlphaServer 4100 HPSS disk & tape Mover HPSS disk & tape Mover HPSS User Forum, Santa Fe CERN IT/PDP
mirror mirror mirror mirror Ultra SCSI Ultra SCSI IBM F50 IBM F50 3590 3590 HPSS Performance HIPPI 25 MB/s HPSS User Forum, Santa Fe CERN IT/PDP
Data currently in HPSS at CERN • Mixed sized files • 1 TB, 15000 files, 60MB average • Raw Experimental Data and Test Beam Files • NA57 raw data: 2 TB, 3000 files (to be repeated) • Atlas Objectivity test data: 1 TB in 2000 files (to be repeated) • CMS 700 GB, 5000 test beam files, 140 MB average • sometimes 3 TB in one day • Total • 10 TB, 65000 files, 100-800 tape mounts / day HPSS User Forum, Santa Fe CERN IT/PDP
Current and Future Work • Ongoing work with HPSS: • ALICE data challenge largely successful, will be repeated • test scalability of the name space to several million files • upgrade to 4.1.1 for new function & Y2K when Encina TX arrives! • Successful service but too soon to commit to HPSS: • Complete COMPAQ port now underway - and Solaris port coming • BABAR started with HPSS & Objectivity so we will learn from them • CERN stager enhancement program (CASTOR) well under way • Will run HPSS till end 2000 with modest expansion and some stress testing to complete evaluation • Limited volume of real data in HPSS could be exported to another system if final decision is to stop HPSS HPSS User Forum, Santa Fe CERN IT/PDP
HPSS Wish List • Short Term • Encina TX series 4.2, so can move/port to HPSS 4.1.1 • Better monitoring information - help with Redwood problems • New changecos option helps, but other improvements needed • Long Term • Non-DCE movers • Movers running on Linux • Improved random access and small-file migration performance • Guaranteed input rate • ways to avoid disk contention problems • number of tape drives dedicated to a COS • avoid stopping PVL etc. to change configuration • multiple HPSS systems on same license HPSS User Forum, Santa Fe CERN IT/PDP