Supercomputers 2

1. CS 147 Lecture 19 Supercomputers 2 Prof. Sin-Min Lee Department of Computer Science

2. Cluster Computers

3. Clusters on the Rise Using clusters of small machines to build a supercomputer is not a new concept. Another of the world's top machines, housed at the Lawrence Livermore National Laboratory, was constructed from 2,304 Xeon processors. The machine was build by Utah-based Linux Networx. Clustering technology has meant that traditional big-iron leaders like Cray (Nasdaq: CRAY) and IBM have new competition from makers of smaller machines. Dell (Nasdaq: DELL) , among other companies, has sold high-powered computing clusters to research institutions.

4. Cluster Computers • Each computer in a cluster is a complete computer by itself • CPU • Memory • Disk • etc • Computers communicate with each other via some interconnection bus

5. Cluster Computers • Typically used where one computer does not have enough capacity to do the expected work • Large Servers • Cheaper than building one GIANT computer

6. Although not new, supercomputing clustering technology still is impressive. It works by farming out chunks of data to individual machines, adding that clustering works better for some types of computing problems than others. For example, a cluster would not be ideal to compete against IBM's Deep Blue supercomputer in a chess match; in this case, all the data must be available to one processor at the same moment -- the machine operates much in the same way as the human brain handles tasks. However, a cluster would be ideal for the processing of seismic data for oil exploration, because that computing job can be divided into many smaller tasks.

7. Cluster Computers • Need to break up work among the computers in the cluster • Example: Microsoft.com Search Engine • 6 computers running SQL Server • Each has a copy of the MS Knowledge Base • Search requests come to one computer • Sends request to one of the 6 • Attempts to keep all 6 busy

8. The Virginia Tech Mac supercomputer should be fully functional and in use by January 2004. It will be used for research into nanoscale electronics, quantum chemistry, computational chemistry, aerodynamics, molecular statics, computational acoustics and the molecular modeling of proteins.

9. Visual Tour

10. Current Cray Products • Cray X1 is the only Cray’s product with a unique vector CPU • Competitors are: Fujitsu, NEC, HP • Cray XT3 and XD1 use AMD Opteron CPUs (series 100 and series 200 accordingly) • You can find full product specifications as well as additional information on current systems at www.cray.com

11. Performance Measurements • Performance is measured in teraflops • Linpack is a standard benchmark • Performance is also measured in memory bandwidth & latency, disk performance, interconnects, internal IO, reliability, and others • For example: • My home system, Athlon 750, gives about 34 megaflops (34*10^6 flops) • Current mid-range supercomputers give about 40 teraflops(40*10^12 flops) which is 1,176,470 times faster

12. Scalable Architecture in XT-3

13. Is Cray a good deal? • Typical Cost approximately $30 million and above • Useful lifetime – 6 years • Most customers use supercomputers at 90% - 98% load • Clustered supercomputers and machines build around common desktop components (AMD/Intel CPUs, memory chips, motherboards, and etc.) are significantly cheaper

14. Future • Cray’s “Red Storm” System in Sandia National Laboratories is running on Linux OS • Current Cost $90 million • Uses 11,648 AMD Opteron CPUs • Current operational speed – 41.5 teraflops • Uses unique SeaStar chip, which passes messages between thousands of CPUs • Upgrades are scheduled to be completed by the end of 2005 using dual-core Opteron • Expected to reach 100 teraflops by the end of 2005

21. Computers and Weather forecasting Weather forecasting

22. Menu Explanation Weather station Radiosonde Overview picture Satellites Data collection Radar Weather ships Sensors Supercomputers Data logging Parallel Processing The Grid System Software Pressing Weather forecasting on any slide will bring you back to this menu Weather forecasting

23. During the last two decades the Met Office has used state-of-the-art supercomputers for numerical weather prediction and more recently, also for predictions of global climate. This is a picture of a supercomputer Weather forecasting

24. Weather forecasting Weather forecasters are helped by several things. These include:- 1. The computer’s advice 2. Information from radar 3. Information from satellite pictures The computer makes millions of calculations. The sums are called differential equations Before the computer can do the calculations, data has to be collected first.

25. Collecting data on the weather is very important. Without the data, the computer could not do the calculations that enable it to make weather predictions. The next slide shows where the data comes from. It also shows where the forecasts are sent. Always remember that the forecasters are highly trained people and they use their judgement and expertise to make their forecast based on the information the computer gives them and the information from the radar and the satellite pictures. Weather forecasting

26. Satellites Radio-sonde Weather stations Radar Weather ship and weather buoys Supercomputer Weather forecasting

27. Satellites Radio-sonde Weather stations Radar Weather ship and weather buoys Supercomputer Aviation Forecaster National and International Forecast Services up to 7 days ahead. Shipping Global forecast services Weather forecasting

28. Satellites Radio-sonde Weather stations Radar Weather ship and weather buoys Supercomputer Aviation Forecaster National and International Forecast Services up to 7 days ahead. Shipping Global forecast services Weather forecasting

29. Data is collected continuously for the computer from the following:- • Weather stations • Automated weather • stations • 3. Satellites • 4. Radar • 5. Radiosondes • 6. Weather ships • 7. Mini-radiosondes • 8. Radar • 9. Aeroplanes • 10. Drifting buoys Weather forecasting

30. The data measurements are made by sensors A sensor is a transducer which responds to some physical property such as pressure, temperature, rate of flow. A transducer is an electronic component which converts energy from one form to another. We want the transducers to send signals to the computer in the Met. Office. Weather forecasting

31. The measurements needed include:- 1. Temperature .. Air, surface and subsurface temp. 2. Atmospheric Pressure 3. Wind speed 4. Wind direction 5. Humidity 6. Rainfall 7. Sunshine Weather forecasting

32. These are some of the sensors used to collect data. Weather forecasting

33. Data logging is the capture and storage of data for future use. All the measurements from the sensors are stored because:- • The computer processes the data in batches • People need to refer back to weather data for • many reasons So data logging is used in weather forecasting. Weather forecasting

34. The next slides explain more about data collection. To jump to the details of the computers, click on the computer. Weather forecasting

35. Radiation from the sun Formation of rain and snow Formation of clouds Radiation from the atmosphere Evaporation and heat exchange Friction Radiation from the earth Mountain effects Sea The atmosphere is split up into a 3-D grid. Each land based grid is about 60km. Weather forecasting

36. The vertical grid you just saw only had 5 levels. The Met Office uses far more, some computer models work on 40 vertical levels. For the global forecasts the horizontal grid is 60km For UK forecasts the horizontal grid is 15km. Weather forecasting

37. We need to measure pressure, temperature, wind speed and wind directions as well as rainfall, cloud cover,etc in as many grid spaces as possible Sea Weather forecasting

38. Sea Weather stations are used here. Weather forecasting

39. A weather station sends signals back to the Met Office computer. The instruments measure pressure, temperature and humidity. Some weather stations are automated. These send their measurements back to the computerdirectly. Picture thanks to Sparholt school who have a great web site www.hants.gov.uk/sparsholtschoolscentre Weather forecasting

40. We need to measure pressure, temperature, wind speed and wind directions as well as rainfall, cloud cover,etc Radiosondes are used up here. 20 km Sea Weather forecasting

41. A radiosonde sends signals back to the Met Office computer. They are attached to a balloon carrying instruments. The instruments measure pressure, temperature and humidity. By measuring the track of the radiosonde, the wind direction and speed can be calculated. Photo courtesy of the British Atmospheric Data Centre Weather forecasting

42. UTC = Universal Time Co-ordinated All over the world, radiosondes are released at midday and midnight UTC. Weather forecasting

43. UTC = Universal Time Co-ordinated UTC is also known as GMT Greenwich Mean Time Baghdad 3 pm Atlantic Daylight 9 am Hawaii 2 am West Australian Standard7 pm Here are some of the times when the radiosondes are released to correspond with the ones in Britain at midday. Weather forecasting

44. We need to measure pressure, temperature, wind speed and wind directions as well as rainfall, cloud cover,etc Minisondes are used here. 5 km Sea Everest is 8.85 Kms high. So we have shown you a very high mountain! Weather forecasting

45. A minisonde system takes measurements at 5Km above sea level. Both radiosondes and minisondes use radio waves to transmit the data readings to the computers Weather forecasting

46. We need to measure pressure, temperature, wind speed and wind directions as well as rainfall, cloud cover,etc Aeroplanes send data too. 10 km Sea Weather forecasting

47. We need to measure pressure, temperature, wind speed and wind directions as well as rainfall, cloud cover,etc 36,000km Satellites send data too. Sea The Geostationary satellites are 36,000 Km above earth. Weather forecasting

48. There are two types of satellites. • Geostationary. These stay in the same spot. • They orbit the earth at exactly the same speed as • the earth rotates. They are very high above earth - • 36,000 km. 5 geostationary satellites are enough to give global coverage. • Polar orbiting. These orbit the earth about 14 • times a day. They orbit at 1000 km above the • earth. Weather forecasting

49. A Geostationary satellite stays in the same place with respect to earth all the time A Polar orbiting satellite moves above the earth’s surface Weather forecasting

50. Picture courtesy of the European Organisation for the Exploitation of Meteorological Satellites and photo courtesy of Dundee University. The satellite’s signals are received by antennae. ©Eumetsat 2003 Meteosat: a geostationary satellite. It sends microwave signals back to earth. The URL ( Uniform Resource Locator ) www.sat.dundee.ac.uk/tour.html will tell you more about satellites if you are interested Weather forecasting