10. Volunteer Computing
P2P-Tuple Architecture Overview
Evaluation Peer Design
Future
. Overall Operation
Step 1: Peers join the overlay and a SCRIBE group.
Step 2: Group owners submit their task to the Tuple Space using a
client program.
(Tasks can also be pipelined)
Step 3: Peers periodically broadcasts task notification
message.
Step 4: Peers in the same group start pulling jobs related to that
task.
Step 5: Notified peers spread the word.
Step 6: Once the job is finished the result is put encoded back on
the Tuple Space.
. . . . . .
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14. Volunteer Computing
P2P-Tuple Architecture Overview
Evaluation Peer Design
Future
. Measures to Achieve Fault Tolerance
Measure: Provide high availability, face high churn rate, remain
reliable.
Effect: Redundancy of data, Replication, use of Erasure Code.
. . . . . .
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15. Volunteer Computing
P2P-Tuple Architecture Overview
Evaluation Peer Design
Future
. Measures to Achieve Fault Tolerance
Measure: Provide high availability, face high churn rate, remain
reliable.
Effect: Redundancy of data, Replication, use of Erasure Code.
Measure: Loss of data from high churn rate
Effect: Communicating Mirrored Replicas of stored objects.
. . . . . .
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16. Volunteer Computing
P2P-Tuple Architecture Overview
Evaluation Peer Design
Future
. Measures to Achieve Fault Tolerance
Measure: Provide high availability, face high churn rate, remain
reliable.
Effect: Redundancy of data, Replication, use of Erasure Code.
Measure: Loss of data from high churn rate
Effect: Communicating Mirrored Replicas of stored objects.
Measure: Untrusted peers, possible low job completion probability.
Effect: Job Duplication using a randomized job scheduling scheme.
. . . . . .
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17. Volunteer Computing
P2P-Tuple Architecture Overview
Evaluation Peer Design
Future
. Measures to Achieve Fault Tolerance
Measure: Provide high availability, face high churn rate, remain
reliable.
Effect: Redundancy of data, Replication, use of Erasure Code.
Measure: Loss of data from high churn rate
Effect: Communicating Mirrored Replicas of stored objects.
Measure: Untrusted peers, possible low job completion probability.
Effect: Job Duplication using a randomized job scheduling scheme.
Measure: Disconnecting Client Application.
Effect: Checkpoints.
. . . . . .
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19. Volunteer Computing
P2P-Tuple Architecture Simulation
Evaluation Results
Future
. Impact of mirrors
.
Result .
..
Using 1 or 2 mirrors extends the duration of the data availability.
.
.. .
.
. . . . . .
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20. Volunteer Computing
P2P-Tuple Architecture Simulation
Evaluation Results
Future
. Impact of Redundancy Level
.
Result .
..
The increase of the duration of data availability is proportionate to
the increase of Redundancy level.
.
.. .
.
. . . . . .
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21. Volunteer Computing
P2P-Tuple Architecture Simulation
Evaluation Results
Future
. Behavior in high churn environment
.
Result .
..
In a high churn rate environment the availability decreases easily.
.
.. .
.
. . . . . .
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