A POTPOURRI OF DISTRIBUTED COMPUTING RESEARCHES. Patrizio Dazzi. lunedì 25 giugno 12

Transcription

1 A POTPOURRI OF DISTRIBUTED COMPUTING RESEARCHES Patrizio Dazzi

2 WHAT DOES DISTRIBUTED MEANS? comes from the latin verb distribuere: dis apart tribuere assign

3 WHAT DOES DISTRIBUTED MEANS? comes from the latin verb distribuere: dis apart tribuere assign

4 ...AND WHAT ABOUT POUTPURRI? Originally was referred to: a mixture of dried petals and spices placed in a bowl or small sack to perfume clothing or a room. However, it currently means also a mixture of things

5 ...AND WHAT ABOUT POUTPURRI? Originally was referred to: a mixture of dried petals and spices placed in a bowl or small sack to perfume clothing or a room. However, it currently means also a mixture of things

6 PATRIZIO S RESEARCH ACTIVITIES Past Activities Grid Programming Models Automated Code Generation for Parallel Computing Semi-current Activities (Meta-)Scheduling Current Activities Epidemic Peer-to-Peer protocols Federation of Clouds

7 PATRIZIO S RESEARCH ACTIVITIES Past Activities Grid Programming Models Automated Code Generation for Parallel Computing Semi-current Activities (Meta-)Scheduling to be continued? Current Activities Epidemic Peer-to-Peer protocols Federation of Clouds

8 PATRIZIO S RESEARCH ACTIVITIES Past Activities Grid Programming Models Automated Code Generation for Parallel Computing Semi-current Activities (Meta-)Scheduling Current Activities to be continued? maybe in a Cloud environment!!! Epidemic Peer-to-Peer protocols Federation of Clouds

9 PATRIZIO S RESEARCH ACTIVITIES Past Activities Grid Programming Models Automated Code Generation for Parallel Computing Semi-current Activities (Meta-)Scheduling to be continued? Current Activities Epidemic Peer-to-Peer protocols Federation of Clouds maybe in a Cloud environment!!! Will be partially presented later by Ranieri Baraglia

10 PATRIZIO S RESEARCH ACTIVITIES Past Activities Grid Programming Models Automated Code Generation for Parallel Computing Semi-current Activities (Meta-)Scheduling Current Activities Epidemic Peer-to-Peer protocols Federation of Clouds to be continued? maybe in a Cloud environment!!! Will be partially presented later by Ranieri Baraglia Will be presented later by Massimo Coppola

11 PATRIZIO S RESEARCH ACTIVITIES Past Activities Grid Programming Models Automated Code Generation for Parallel Computing Semi-current Activities (Meta-)Scheduling Current Activities Epidemic Peer-to-Peer protocols Federation of Clouds to be continued? maybe in a Cloud environment!!! Will be partially presented later by Ranieri Baraglia Will be presented later by Massimo Coppola

12 RESEARCH ISSUES AND GOALS (Meta-)Scheduling Distributed environment Huge amount of resources Huge amount of applications to run Multi-constraints Multi-criteria Epidemic Peer-to-Peer protocols Distributed Environment Thousands of machines No central authority Information Diffusion and Aggregation NP-complete Scalable Solutions Cost-effective approaches Robust Solutions Limit the amount of traffic generated

13 (META-)SCHEDULING Solutions targeting the scheduling of streams of batch jobs on big computing farms given optimality criterion applications/environment constraints and requirements Two approaches: Convergent Scheduling A Multi-criteria Class-based Job Scheduler

14 CONVERGENT SCHEDULING Based on a set of heuristics to manage problem constraints each heuristics contributes to compute the matching value such value specifies a degree of matching between a job and a machine Heuristic 1 Heuristic 2 Heuristic 3 Jobs/ Machines Matrix Heuristic 4

15 A MULTI-CRITERIA CLASS- BASED JOB SCHEDULER Three-layer scheduler Job Dispatcher Control Scheduler Class Scheduler

16 EPIDEMIC (OR GOSSIP) PROTOCOLS synonym because: gossip spreads information in a manner similar to the spread of a virus in a biological community convenient because: robust (reliable communications are not assumed) cheap (information exchanged during the interactions is of bounded size)

17 ACTIVE AND PASSIVE EPIDEMIC BEHAVIOR Active Thread Passive Thread // Runs periodically every T time units 1. q = selectpeer() 2. myitem = (myaddress, timenow, myfilelist) 3. buf_send = selectitemstosend() 4. send buf_send to q 5. receive buf_recv from q 6. view = selectitemstokeep() // Runs when contacted by some peer 1. receive buf_recv from p 2. myitem = (myaddress, timenow, myfilelist) 3. buf_send = selectitemstosend() 4. send buf_send to p 5. view = selectitemstokeep()

18 EPIDEMIC PROTOCOLS: MAIN APPLICATIONS Overlay Building for: Information Diffusion flooding the network but producing bounded worst-case loads useful for realizing: event dissemination protocols background data dissemination protocols Information Aggregation organizing each peer neighborhood on the basis of a given goal

19 EPIDEMIC PROTOCOLS AS BUILDING BLOCKS Epidemic/Gossip protocols can be: layered composed used underneath other protocols

20 EPIDEMIC PROTOCOLS AS BUILDING BLOCKS Epidemic/Gossip protocols can be: layered composed Two our solutions used underneath other protocols{group GODEL

21 EPIDEMIC PROTOCOLS AS BUILDING BLOCKS Epidemic/Gossip protocols can be: layered composed Two our solutions used underneath other protocols{group GODEL Presented later by Ranieri

22 GODEL: GOSSIP DELAUNAY Given a set P of points, a Delaunay triangulation is a triangulation DT(P) such that no point in P is inside the circumcircle of any triangle. Delaunay triangulations maximize the minimum angle of all the angles of the triangles in the triangulation. Delaunay triangulations support efficient routing and data broadcasting potential applications include DVEs and Geographical Nearest Neighbors Selection Godel Build a Delaunay triangulation in a incremental and totally decentralized way Exploits Cyclon (Random Peer Sampling) and Vicinity (Similarity-based Peer Sampling) for gathering information about near peers Each node executes a test to check if a node received from the gossip level is its Delanuay neighbour. The neighbour test is based on the empty circumcircle property.

23 FUTURE IDEAS (Meta-)Scheduling targeting cloud environments considering power consumption considering complex price policies managing co-allocation managing always-active applications targeting federations of clouds Epidemic Peer-to-Peer protocols generalization of the layering definition of a core set of epidemic protocols experiment different kinds of spatial representation exploiting more complex approaches for neighbor selection

24 THANK YOU FOR YOUR ATTENTION!!! Questions

25 THANK YOU FOR YOUR ATTENTION!!! Questions Look behind you!! A three-headed monkey!!!