Trends and Directions of Mass Storage in the Scientific Computing Arena CAS 2001

1. Trends and Directions of Mass Storage in the Scientific Computing ArenaCAS 2001 Gene Harano National Center for Atmospheric Research

3. Vision • How do we accomplish that vision? • Handling large datasets – Analysis and Visualization • Shared File Systems and Cache Pools • Middleware and layering • Management tools • Emerging Technologies • (To name a few)

4. Large Datasets • The NCAR MSS was originally a tape based archive. • NCAR MSS average file size is 35 MBs (11 M files); small due to historical restrictions (single volume datasets, model history files) and a large number (25%) of files < 1 MB (user backups) • Single TB sized files are common for visualization and analysis • Currently these large files are sliced up prior to landing in the archive. • Access is generally sequential, but some random access.

5. Large Datasets • Are tape based archives obsolete? • No, but there is a need to reevaluate the entire storage structure at NCAR. • Cache pools • Data warehouses, data sub-setting • The NCAR MSS is being treated as a shared file system rather than an archive.

6. Shared File System Web/ GRID/ servers • Heterogeneous • High-Performance • High-Capacity • Doesn’t yet exist. Programmatic Shared Data Command Line

7. Cache Pools • External to the archive • Minimize archive activity • Temporary data stays out of the archive • Customized for a smaller set of associated data • Internal to the archive • Minimize tape activity • Improve response time • Federate and distribute • Repackage small files for tape storage under system control

8. Terascale Modeling & Analysis Advanced Research Computing System (IBM SP) MSS Proxy Data analysis GPFS Shared File System

9. Terascale Analysis & Visualization Vislab MSS Proxy Data analysis Storage Area Network Shared File System

10. Data Provisioning & Access MSS Proxy Data Processor Unidata, DODs DSS server CDP/ESG Storage Area Network Shared File System

11. Internal Cache Pools • NCAR MSS event log modeling (April 2000 – April 2001) – looking at tape activity • 20 TB cache pool – can be federated and distributed • 30 day average cache residency • 70% reduction in tape read-backs • Greatly enhanced response time • Reduce the amount of tape resources or redefine their use.

12. Middleware and Layering Role of an archive • An Archive performs 2 basic functions • Reliably storing data • Returning data on demand • Data analysis, data mining, data assimilation, distributed data servers, etc. are functions utilizing middleware that sits on top of an archive and should be implemented independent of the underlying archive.

13. Middleware and Layering • Separate archive functionality from • Visualization • Data servers • Data warehousing, data mining, data subsetting • Web and Grid access • Etc. • Maximally enables the use of COTS • Allows (transparent) replacement of components as needed • Fill the gaps with custom software

14. Future Data Services NCAR MSS Archive WEB Visualization Data Analysis/Mining/Assimilation Digital Libraries, Data Servers Data Cataloging/ Searching Data Storage Data Storage File Cache Services Pools

15. Management Tools • There is a need for better user and system management tools as MSS capacity scales. • How does a single user manage 1 million files? • How does a MSS administrator dynamically tune a system, predict workloads, find and correct bottlenecks?

16. Management Tools NCAR MSS tools • Defining new roles • Single ordinary user • MSS superuser • As users come and go, there is a need for: • Project superuser (new) • Division data administrator (new) • Web based metadata user tools • List, search, catalog holdings – metadata mining • Remove unwanted files

17. Management Tools NCAR MSS tools • From the system perspective – utilize data warehousing and data mining techniques • System modeling using event logs. • Capacity planning • Identify bottlenecks • Operational monitoring • Track errors, identify trends (media problems) • Intrusion detection • Dynamic system tuning

18. Emerging Technologies • Data Path • Tape • Holographic Storage • Probe-Based MEMS • High-Density Rosetta (analog)

19. Data Path • HIPPI in use today in the NCAR archive • Fibre Channel will replace our HIPPI in the near term • FC SAN for RAID Cache Pools • FC SAN for Tape sharing • Others • iSCSI • FC over IP • Infiniband

20. Tape 1 TB,60MB,2004 2H02 200GB 1Q02 500GB 2003 Opt 2003 1 TB 9840B DTF 3590E SD-3 Mammoth 2 3570C 3590 Ultrium 2001 9940 9840 AIT-2 Accelis SDLT 9490 EE Mammoth DLT-7000 3490 E AIT 3570 DLT-4000 3480/90 Native Cartridge Capacity (GB) Linear Helical

21. Tape • To be competitive with magnetic disk, magnetic tape must grow at 10x each 5 years. • Achieved by a combination of increased areal density and longer (and possibly wider) tape. (from a storage vendor)

22. Tape • RAIT (Redundant Array of Independent Tapes) • Increased Performance • Higher Reliability with the use of parity • Higher single “volume” Capacity • Large datasets on a single “volume” • RAIL (Redundant Array of Independent Libraries) • Greater total system capacity • Improved response time • These are resource intensive solutions – dedicated libraries and drives

23. Holographic • Large capacity – 10 GBs in a single cubic centimeter (10 Gbits/in2 for magnetic disk) • High-speed – 2 Gigabits/sec • Low power • Billions of write cycles

24. Probe-Based MEMS • MEMS – Micro-Electrical Mechanical Systems • Probe-based storage arrays • Dense • Highly parallel to achieve high bandwidth • Rectilinear 2D positioning • Commercial devices in the next several years

25. HD Rosetta • Product marketed by Norsam Technologies • Developed at Los Alamos National Lab • Analog • Lifetime of 1000s of years • Can be read back with only a microscope • Stores text and images