1. INFSO-RI-508833 Enabling Grids for E-sciencE www.eu-egee.org GridICE: a monitoring service for Grid Systems Sergio Andreozzi INFN (Italy) sergio.andreozzi@cnaf.infn.it TERENA Networking Conference 2005, 8 June

2. Enabling Grids for E-sciencE INFSO-RI-508833 TNC2005, Poznan, 8 june 2005 2 OUTLINE What is a Grid What is Monitoring –terms and concepts –the process of monitoring Use cases for a Grid Monitoring System GridICE –Architecture –Screenshots

3. Enabling Grids for E-sciencE INFSO-RI-508833 TNC2005, Poznan, 8 june 2005 3 What is a Grid Virtualization of users and resources Site A Site B Grid system Mapping virtual resources to physical resources Mapping virtual users to physical users

4. Enabling Grids for E-sciencE INFSO-RI-508833 TNC2005, Poznan, 8 june 2005 4 What is a Grid Grid Systems: enable the secure sharing of resources (e.g., execution environments for jobs, storage areas, databases) Shared resources –Can be geographically dispersed –Can be heterogeneous –Can belong to different administrative domains –Their composition can dynamically change –Can be accessed by remote users

5. Enabling Grids for E-sciencE INFSO-RI-508833 TNC2005, Poznan, 8 june 2005 5 What is Monitoring Terms and Concepts Grid Monitoring –the activity of measuring significant grid resources related parameters –in order to  analyze usage, behavior and performance of the grid  detect and notify fault situations contract violations (SLA) user-defined events

6. Enabling Grids for E-sciencE INFSO-RI-508833 TNC2005, Poznan, 8 june 2005 6 What is Monitoring Terms and Concepts Measurement: the process by which numbers or symbols are assigned to feature of an entity in order to describe them according to clearly defined rules Event: collection of timestamped data associated with the attribute of an entity [2] Event schema (or simply schema): defines the typed structure and semantics of all events so that, given an event type, one can find the structure and interpret the semantics of the corresponding event [2]

7. Enabling Grids for E-sciencE INFSO-RI-508833 TNC2005, Poznan, 8 june 2005 7 The four main phases of monitoring Generation Distributing Presenting Processing sensors enquiring entities and encoding the measurements according to a schema (active/passive, intrusive/non-intrusive) transmission of the events from the source to any interested parties (data delivery model: push vs. pull; periodic vs. aperiodic; unicast vs. l-to-N) Processing and abstract the number of received events in order to enable a the consumer to draw conclusions about the operation of the monitored system e.g., filtering according to some predefined criteria, or summarising a group of events

8. Enabling Grids for E-sciencE INFSO-RI-508833 TNC2005, Poznan, 8 june 2005 8 Use cases for Grid monitoring Virtual Organization: 1.visualize at various aggregation levels the actual set of resources accessible to its members; 2.Assess how Grid mapping functionalities from virtual to physical resources and users meet the members’ demands 3.analyze data retrospectively to understand how to improve the effectiveness of VO applications running in a Grid, as the target machine for different executions of the same application can vary over time

9. Enabling Grids for E-sciencE INFSO-RI-508833 TNC2005, Poznan, 8 june 2005 9 Use cases for Grid monitoring Site Administrator: –Visualize the managed Grid services in order to see how they are being used/performing (possibly divided by VO) User: –Is my job “working” (e.g., consuming CPU?) Grid Operation Center: –Status of Grid services (e.g., WMS, Service Discovery, CE, SE) –Free/busy resources per site/per VO at a given time –Timely notification about fault situations

10. Enabling Grids for E-sciencE INFSO-RI-508833 TNC2005, Poznan, 8 june 2005 10 GridICE: architectural insight

11. Enabling Grids for E-sciencE INFSO-RI-508833 TNC2005, Poznan, 8 june 2005 11 Monitoring: generating events generation of events: –Sensors: typically perl scripts or c programs –Schema:  GLUE Schema v.1.1 + GridICE extension System related (e.g., CPU load, CPU Type, Memory size) Grid service related (e.g., CE ID, queued jobs) Network related (e.g., Packet loss) [5] Job usage (e.g., CPU Time, Wall Time) –All sensors are executed in a periodic fashion

12. Enabling Grids for E-sciencE INFSO-RI-508833 TNC2005, Poznan, 8 june 2005 12 Monitoring: distributing distribution of events: –Hierarchical model  Intra-site: by means of the local monitoring service default choice, LEMON (http://www.cern.ch/lemon)  Inter-site: by offering data through the Grid Information Service  Final Consumer: depending on the client application –Mixed data delivery model  Intra-site: depending on the local monitoring service (push for lemon)  Inter-site: depending on the GIS (current choice, MDS 2.x, pull)  Final consumer: pull (browser/application), push (publish/subscribe notification service)

13. Enabling Grids for E-sciencE INFSO-RI-508833 TNC2005, Poznan, 8 june 2005 13 Example deployment in LCG2

14. Enabling Grids for E-sciencE INFSO-RI-508833 TNC2005, Poznan, 8 june 2005 14 GridICE Architecture ResourceSite Publisher Sensor event collector event provider consumer publisher WAN LAN publishers Lemon srv Lemon agt LDAP Client MDS GRIS scripts HTTP: HTML/XML NS GridICE on LCG 2logical componentsroles GridICE ServerConsumer WAN xML: pull,aperiodic,unicast NS: push,aperiodic,unicast Browser Data delivery model pull,periodic,unicast push,periodic,unicast application consumers

15. Enabling Grids for E-sciencE INFSO-RI-508833 TNC2005, Poznan, 8 june 2005 15 GridICE on gLite Resource Site Publisher Sensor event collector event provider consumer publisher WAN LAN publishers Lemon srv Lemon agent CEMon scripts HTTP: HTML/XML NS GridICE on gLitelogical componentsroles GridICE Server Consumer WAN xML: pull,aperiodic,unicast NS: push,aperiodic,unicast Browser Data delivery model pull,periodic,unicast push,periodic,unicast RGMA application consumers MDS2 consumers G

16. Enabling Grids for E-sciencE INFSO-RI-508833 TNC2005, Poznan, 8 june 2005 16 GridICE Server Persistent storage DiscoveryConsumersScheduler XSLT->HTML XML abstraction XMLNotification S.Charts components that need to be revised when migrating to gLite [6]

17. Enabling Grids for E-sciencE INFSO-RI-508833 TNC2005, Poznan, 8 june 2005 17 GridICE >> Site View >> General

18. Enabling Grids for E-sciencE INFSO-RI-508833 TNC2005, Poznan, 8 june 2005 18 GridICE >> Site View >> Host Summary

19. Enabling Grids for E-sciencE INFSO-RI-508833 TNC2005, Poznan, 8 june 2005 19 Running/waiting jobs for a VO

20. Enabling Grids for E-sciencE INFSO-RI-508833 TNC2005, Poznan, 8 june 2005 20 Current release status –Integrated and deployed with LCG 2.x –Last server release v.1.8.0.rc1 –Last sensor release v.1.5.1.pl2 –Installed servers are monitoring Grid resources in the scope of:  Grid.it  GILDA  LCG  LCG South-West federation  LCG South-East federation  SEE-GRID  E-grid project  CMS experiment  ATLAS experiment

21. Enabling Grids for E-sciencE INFSO-RI-508833 TNC2005, Poznan, 8 june 2005 21 Next steps Avoid proliferation of sensors (especially for intrusive ones) –Planned integrated with metering system of DGAS (Grid accounting) Dealing with site policies as regards privacy of log files –Sensors should provide mechanisms to allow sites to push the data of interest Enable security of monitoring data –in particular, VO and role based authorization at the producer levels (e.g., the VO manager of CMS can read all info about the jobs that are running by CMS users) Dealing with heterogeneous producer interfaces Provide a more flexible job monitoring mechanism

22. Enabling Grids for E-sciencE INFSO-RI-508833 TNC2005, Poznan, 8 june 2005 22 CONCLUSION Monitoring of Grid systems is a complex activity in metering, distributing and presenting GridICE has been designed on the basis of the requirements collected by a wide variety of users The experience in production environments is positive New challenges for the evolution in the context of gLite are harmonization of metering, security and dealing with multiple producers

23. Enabling Grids for E-sciencE INFSO-RI-508833 TNC2005, Poznan, 8 june 2005 23 References [1] S. Andreozzia, N. De Bortoli, S. Fantinel, A. Ghiselli, G. L. Rubini, G. Tortone, M. C. Vistoli GridICE: a monitoring service for Grid systems, Future Generation Computer System 21 (2005) 559–571 [2] B. Tierney, R. Aydt, D. Gunter, W. Smith, M. Swany, V. Taylor, R. Wolski, A Grid Monitoring Architecture, GFD-I.7 [3] S. Zanikolas, R. Sakellariou, A taxonomy of grid monitoring systems, Future Generation Computer Systems 21 (2005) 163–188 [4] M. Franklin, S. Zdonik, “Data In Your Face”: Push Technology in Perspective, ACM SIGMOD ’98, Seattle, WA, USA [5] S. Andreozzi, A. Ciuffoletti, A. Ghiselli, C. Vistoli. Monitoring the connectivity of a Grid. Proceedings of the 2nd International Workshop on Middleware for Grid Computing (MGC 2004) in conjunction with the 5th ACM/IFIP/USENIX International Middleware Conference, Toronto, Canada, October 2004. [6] S. Andreozzi, N. De Bortoli, S. Fantinel, G.L. Rubini, G. Tortone. Design and Implementation of a Notification Model for Grid Monitoring Events. CHEP04, Interlaken (CH), Sep 2004 Dissemination: http://grid.infn.it/gridicehttp://grid.infn.it/gridice