1 / 10

Sharing Memory in a Self-stabilizing Manner

Sharing Memory in a Self-stabilizing Manner. Noga Alon , Hagit Attiya , Shlomi Dolev , Swan Dubios , Maria Gradinariu , Sebastien Tixeuil DISC, 2010. Talk Outline. Bounded Time Stamp Guessing Game Quorum System Integration. Quorum Based SWMR. Writer has a sequence number seq

carol-alford
Download Presentation

Sharing Memory in a Self-stabilizing Manner

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Sharing Memory in a Self-stabilizing Manner NogaAlon, HagitAttiya, ShlomiDolev, Swan Dubios, Maria Gradinariu, SebastienTixeuil DISC, 2010

  2. Talk Outline Bounded Time Stamp Guessing Game Quorum System Integration

  3. Quorum Based SWMR • Writer has a sequence number seq • Sends messages to all the participants with NewValue seq+1 • The write of NewValue terminates, once acknowledged by more than half of the participants • (Fast) Self-stabilizing, for unbounded seq, first ask for the largest seq known to the participants

  4. Bounded Time Stamps • {Sting, (AntiSting1, Antisting2,…, AntistingK)} • {3,(4,5,7)} > {4,(2,10,5)} • {3,(4,5,7)} ? {4,(3,10,5)} Given any K timestamps, a timestamp greater than them all can be constructed. Take all the K stings as Antistings and non existing value as a sting.

  5. Guessing Game • Hiderhides H (ts1, ts2,…,tsH) timestamps unknown to the finder

  6. Guessing Game • Hiderhides H (ts1, ts2,…,tsH) timestamps unknown to the finder • Finder would like to introduce a timestamp tsF greater than all the H (unrevealed timestamps) • Finder introduces a timestamp tsF the Hiderpulls out tsIfrom (ts1, ts2,...,tsH) not smaller than tsFand may replace tsI by tsFin (ts1, ts2,…,tsH) • Finder repeatedlytries, • Does the Finder have a winning strategy?

  7. Guessing Game • Finder maintains a fifo Queue of 2H timestamps

  8. Guessing Game • Finder maintains a fifo Queue of 2H timestamps • Introduces a timetamp tsF greater than all the timestamps in the Queue • Whenever theHider reveals a non smaller timestamp tsI, both tsF and tsI are enqueued. • The FinderWINS! • After at most H turns.

  9. Quorum Systems for SWMR • Label is a timestamp (epoch) and sequence number (tsF,sn) • The sequence number starts in 1 and grows until 2^64… practically infinite • Finder is the writer that introduces a new epoch (tsF) every time a non smaller epoch is found. • Writer increments the sequence number and uses it (within the same epoch) as the time stamp for a new value for the SWMR value…

  10. Thank You!

More Related