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Fixed typo #6498

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merged 1 commit into from Jul 30, 2020
Merged

Fixed typo #6498

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2 changes: 1 addition & 1 deletion doc/TwoPhaseCommitDesign.md
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Expand Up @@ -142,7 +142,7 @@ The detailed design explains all the functionalities and interactions.

Currently, transaction ids are issued by VTTablets (VTID), and those ids are considered local. In order to coordinate distributed transactions, a new system is needed to identify and track them. This is needed mainly so that the watchdog process can pick up an orphaned transaction and resolve it to completion.

The DTID will be generated by taking the VTID of the MM and prefixing it with the keyspace, shard info and a sequence to prevent to prevent collisions. If the MM’s VTID was ‘1234’ for keyspace ‘order’ and shard ‘40-80’, then the DTID would be ‘order:40-80:1234’. A collision could still happen if there is a failover and the new vttablet’s starting VTID had overlaps with the previous instance. To prevent this, the starting VTID of the vttablet will be adjusted to a value higher than any used by the prepared GTIDs.
The DTID will be generated by taking the VTID of the MM and prefixing it with the keyspace, shard info and a sequence to prevent collisions. If the MM’s VTID was ‘1234’ for keyspace ‘order’ and shard ‘40-80’, then the DTID would be ‘order:40-80:1234’. A collision could still happen if there is a failover and the new vttablet’s starting VTID had overlaps with the previous instance. To prevent this, the starting VTID of the vttablet will be adjusted to a value higher than any used by the prepared GTIDs.

## Prepare API

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