NODE CLUSTER SYNCHRONIZATION

• US 20170006097A1
• Filed: 01/16/2014
• Published: 01/05/2017
• Est. Priority Date: 01/16/2014
• Status: Active Grant

• Current Assignee: Hewlett Packard Enterprise Development LP (Hewlett-Packard Enterprise Company)
• Original Assignee: Hewlett Packard Enterprise Development LP (Hewlett-Packard Enterprise Company)
• Inventors: Johnson, Charles Stuart
• Granted Patent: US 10,212,226 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G06F 11/1482 by means of middleware or OS functionality
• CPC Class Codes: G06F 11/1691 using a quantum
• CPC Class Codes: H04L 65/611 for multicast or broadcast systems for broadcast or conference H04L12/18; arrangements for broadcast or distribution combined with broadcast H04H20/00; arrangements for broadcast applications with a direct linkage to broadcast information or to broadcast space-time H04H60/00; selective distribution of broadcast services, e.g. multimedia broadcast multicast service [MBMS], H04W4/06
• CPC Class Codes: H04L 67/1095 Replication or mirroring of data, e.g. scheduling or transport for data synchronisation between network nodes
• CPC Class Codes: H04L 7/0016 correction of synchronization errors
• CPC Class Codes: H04L 7/042 Detectors therefor, e.g. correlators, state machines digital correlators in general G06F17/15

Abstract

Systems and methods associated with computing cluster synchronization are disclosed. One example method includes periodically requesting timing values from a set of notes in a computing cluster. The method also includes receiving timing values from members of the set of nodes. The method also includes providing a synchronization value to members of the set of nodes. The synchronization value may be generated based on the timing values. Additionally, the synchronization value may be used to order events across the members.

Claims

1. A computer-implemented method, comprising:

periodically requesting timing values from a set of nodes in a computing cluster;

receiving timing values from members of the set of nodes; and

providing a synchronization value to members of the set of nodes,

where the synchronization value is generated based on the timing values, and where the synchronization value is used to order events across the members of the set of nodes.

2. The computer-implemented method of claim 1, where timing values are Lamport clock values.

3. The computer-implemented method of claim 1, comprising:

receiving acknowledgements of receipt of the synchronization value from members of the set of nodes.

4. The computer-implemented method of claim 3,

where the timing values are requested using a multicast signal and received via unicast replies,

the synchronization value is provided using a multicast signal, and

the acknowledgements are received via unicast acknowledgments.

5. The computer-implemented method of claim 3, where a node failure remedy is taken when a timing value is not received from a member of the set of nodes within a certain period of time after requesting the timing values, or when an acknowledgement is not received from a member of the set of nodes within a certain period of time after providing the synchronization value.

6. The computer-implemented method of claim 5, where the node failure remedy is one of, resending the request for the timing value from the member of the set of nodes and resending the synchronization value to the member of the set of nodes.

7. computer-implemented method of claim 5, where the node failure remedy comprises:

identifying an epoch during which a node failure occurred based on the synchronization value;

restoring members of the set of nodes to a state from prior to the epoch;

determining an ordering of events that took place dun during the epoch; and

re-performing the events based on the ordering of the events.

8. A cluster system, comprising:

a set of computing nodes, each computing node having a Lamport clock;

an

a synchronization logic to request Lamport clock values from the Lamport clock of each computing node and to provide a synchronization value to the nodes in the set of nodes based on the Lamport clock values.

9. The system of claim 8, comprising a recovery logic to take a remedial action when the synchronization logic fails to obtain a Lamport clock value from a node after a period of time.

10. The system of claim 8, where they synchronization logic periodically alternates between requesting the Lamport clock values and providing the synchronization value to create epoch divisions that the nodes use to create a partial ordering of events occurring on the nodes.

11. The system of claim 10, where the synchronization logic introduces a delay between requesting actions and providing actions to increase sizes of epochs.

12. The system of claim where the synchronization logic

requests the Lamport clock values in response to a signal received from an upstream synchronization logic,

provides data to the upstream synchronization logic based on the Lamport clock values, and

provides the synchronization value to the nodes based on data received from the upstream synchronization logic,

where the data is generated based on the Lamport clock values.

13. A non-transitory computer-readable medium storing computer-executable instructions that when executed by a computer cause the computer to:

periodically provide a global sequence number to a set of nodes, where the global sequence number is generated as a function of Lamport clock values obtained from members of the set of nodes.

14. The non-transitory computer-readable medium of claim 13,

where global sequence numbers identify sequential epochs during which events occur on members of the set of nodes, and

where a first event precedes a second event when an epoch associated with the second event exceeds an epoch associated with the first event by more than one epoch.