1. Norwegian Meteorological Institute METNO WDB Weather and Water Database 19 th EGOWS Meeting, Ljubljana, June 9-12, 2008.

2. Norwegian Meteorological Institute METNO Outline Introduction Background of WDB Overview of WDB WDB Components Future of WDB

3. Norwegian Meteorological Institute METNO Who are we? Michael Akinde –Ph.D., Database Architect, IT, Met.no –Systems architect on ROAD system at SMHI(2003-2006) Vegard Bønes –M.Sc., Senior Engineer, IT, Met.no Børge Moe –M.Sc., Senior Engineer, IT, Met.no

4. Norwegian Meteorological Institute METNO Who are you? Survey: please raise your hands... –Who has coded programs? –Who has written SQL queries? –Who has worked with database APIs (JDBC,ODBC,etc)? –Who knows what database normalization is? –Who knows what a database index is? –Who has written database extensions?

5. Norwegian Meteorological Institute METNO What is this about? We need to store weather/water data We need indexed (fast) access to time series retrieved from multiple files or sources We need access from a variety of applications We need products to be consistent We want to be able to track changes We want programs to be independent of the data format We have limited ressources

6. Norwegian Meteorological Institute METNO What is WDB? WDB is a storage system for meteorological, hydrological, and oceanographic data –Developed by the PROFF program at met.no –Based on the ROAD (SMHI) architecture

7. Norwegian Meteorological Institute METNO History of ROAD Operational meteorological database, developed in the late 90’s at SMHI; operational since 2001 Responsible for 90% of SMHI’s automatic production One of the world’s fastest meteorological databases Mature and well-established production system; 3rd generation in development 2006-2008

8. Norwegian Meteorological Institute METNO Problems of ROAD Like most met systems, ROAD is a legacy system –Prior to ROAD3G, the loading chain of the ROAD system included Fortran code developed in the 1970s SMHI is in the process of a major rehaul of the production systems in terms of migrating software from OpenVMS to Linux IBM Informix platform –Geodetic datablade (geospatial extension) –Licenses are expensive

9. Norwegian Meteorological Institute METNO WDB is… Open source collaboration between met.no and SMHI Can be considered the 4th generation of the ROAD system –Built from the ground up without legacy code –Developed at met.no Released under the GNU GPL2 license Fast, Free, Flexible

10. Norwegian Meteorological Institute METNO WDB: Open Source Alternative Should be robust enough to handle high volume, high availability production –e.g., as the backend engine of yr.no Should be flexible –e.g., to easily handle new types of data Should support quality and consistency of data Should be simple to use Should be easy to maintain and operate

11. Norwegian Meteorological Institute METNO WDB provides... Quick and easy to deploy data storage system Modular loading programs –Easy to add more… Data-independent application programmers interface (API) –Usable, in theory, from any environment Fast performance on queries

12. Norwegian Meteorological Institute METNO WDB Overview

13. Norwegian Meteorological Institute METNO Installing WDB Download the tar package, and... Or request the debian package server:wdb-x.x%./configure --prefix=/home/myuser/local server:wdb-x.x% make server:wdb-x.x% make install

14. Norwegian Meteorological Institute METNO Putting WDB through its paces WDB implements all the standard GNU targets “make check” runs the WDB unit tests –tests that can be run without being installed “make installcheck” runs the WDB install tests –tests that require an installed database 300+ tests and counting –CPPunit and TAP protocol –Fully automated test framework on CruiseControl

15. Norwegian Meteorological Institute METNO Enabling Technology Linux (Debian, Fedora Core 5) PostgreSQL version 8.1.x or later PostGIS version 1.1.x or later Proj.4 version 4.6.0 ECMWF GRIB API GNU Autotools C++ open source libraries –Boost Std Libraries, log4cpp, cppunit, etc.

16. Norwegian Meteorological Institute METNO WDB Overview

17. Norwegian Meteorological Institute METNO Loading forecast data Loading data into the database, is as simple as: server:mydata% gribLoad myforecast.grib server:mydata% server:mydata% gribLoad /opdata/hirlam10/*.grib server:mydata%

18. Norwegian Meteorological Institute METNO Loading Programs GRIBLoad is the design pattern for the WDB loading programs Loads one or more GRIB1 files into the database –Uses ECMWF GRIB API, so theoretically, GRIB2 works as well –Stand-alone client program that connects to any WDB database Loaders for other grid formats are easily built in the same way by reusing code Loading of BUFR will be ported from ROAD

19. Norwegian Meteorological Institute METNO WDB Overview

20. Norwegian Meteorological Institute METNO WDB Call Interface (WCI) WCI is the data retrieval API for WDB Based on a function interface in SQL Why not stick to “simple” SQL? - SQL isn't really that simple - Requires knowledge of the underlying data model (tables/views) - Lacks useful functionality; e.g., interpolation, point-in-field, etc.

21. Norwegian Meteorological Institute METNO WCI versus pure SQL SQL results in tight coupling between application and database –Table names –Table structure (attributes) –Really strange database queries

22. Norwegian Meteorological Institute METNO WDB Call Interface (WCI) WCI is the data retrieval API for WDB Based on a function interface in SQL Why not a lib file? - Changes in a library require that the applications using the library are recompiled - New libraries need to be pushed to the user (application) - Each operating system, machine and language = its own library

23. Norwegian Meteorological Institute METNO WCI versus compiled software library How many combinations do we need? Java C C++ Perl Fortran Python Debian Fedora Ubuntu Sun Solaris Windows XP Windows Vista Don't forget 32 vs 64 bit architectures...

24. Norwegian Meteorological Institute METNO WDB Call Interface Features Stable Interface Performance –100-1000 values/s in single point retrieval (to be improved) –10 million floating points/s in field retrieval (about 100 fields/s) Functionality: –Pointwise, Timeseries, 2d-volumes, Quality information –Coming: Paths, Interpolation in space and time, 3D volumes? Easy to program –1/2 page of code to retrieve MHO-data Platforms: C/C++, Java, Perl, Python, Fortran, ODBC… Operating systems: Pretty much anything...

25. Norwegian Meteorological Institute METNO WCI functions wci.begin wci.end wci.read wci.write wci.browse wci.info –Programmer doesn’t need any knowledge of the data format or the database model

26. Norwegian Meteorological Institute METNO The WCI Data Model Data Provider Data Value Place Time (Ref) Time (Valid)Parameter Level Version Quality Value ID??

27. Norwegian Meteorological Institute METNO WDB Overview

28. Norwegian Meteorological Institute METNO WDB2TS TS2XML for WDB Web service to retrieve time series of data from a WDB database –delivers data as csv or xml –REST-like interface http://host/path?lat=10;lon=10;parameterspec (parameterspec = data specification)

29. Norwegian Meteorological Institute METNO The Road ahead for WDB WDB version 0.6.0 –First production version of WDB –Hindcast archive (12 TBs of grids) WDB version 0.7.4 –To be released next week –We currently release a new version about once a month –Implements a new loading program FELT: met.no field format Approximate time to develop: 2 weeks x 2 persons

30. Norwegian Meteorological Institute METNO WDB Roadmap Version 0.8.0 is scheduled for July 2008 –Official beta version of WDB –Limited scale real-time production Version 0.9.0 is scheduled for October 2008 –Release candidate version (full-scale testing) Version 1.0 scheduled for December 2008 –Full-scale production version WDB is a part of the PROFF framework; minimum expected life-time is at least15 years

31. Norwegian Meteorological Institute METNO Future thoughts? Complete integration with Diana More data types –Fields (NetCDF, GRIB2, etc.) –Observations (BUFR, XML) Better administration tools Verified Stability –24x7 hands-free operation (have this in ROAD…) Improved Performance –We have not started optimizations

32. Norwegian Meteorological Institute METNO Future thoughts? Scalability and fail-over –Want more load? Add another server –Want to guarantee up-time? Add more servers Consistency –Easy on one server; we want multiple servers –Distributed data/replication is a well-known problem in the database community –Problems: huge data, geographically distant regions Tracking of changes –Metadata can be used to track history…

33. Norwegian Meteorological Institute METNO Recommended Reading WDB website (wdb.met.no) –WDB User Manual –WCI User Manual –Man Pages for all WDB utilities –Source code browser (SVN repository and doxygen) –Developer documentation (design docs) –Eclipse setup instructions Subscribe to WDB project on Freshmeat.net

34. Norwegian Meteorological Institute METNO Summary WDB is designed as a generic weather/water database system –Perspective: one core system that can be leveraged for many different uses –Functionality that isn't implemented can probably be added –For users: fast access to data –For developers: a simple, generic interface to all kinds of different data –For operators: a system that is easy to maintain

35. Norwegian Meteorological Institute METNO Concluding thoughts… Many, many more WDB systems in the future –WDB is intended as the backbone of the production systems at met.no and SMHI Open source is a different model of collaboration which can be of great benefit to meteorological institutions –We all require broadly the same functionality –Good communications = better systems –Free as in Freedom

36. Norwegian Meteorological Institute METNO THANK YOU ! Questions? E-mail: michael.akinde@met.no