Changing concurrency control modes
AssigneeHewlett Packard Enterprise Development LP
InventorsHuanchen Zhang, Kimberly Keeton
Life of this patent
Estimating the term…
Abstract
Example implementations relate to changing concurrency control modes. An example implementation includes controlling a concurrency control mode of a data slot that stores a data value. A concurrency control mode of a data slot may be changed from an optimistic concurrency control mode to a multi-version concurrency control mode responsive to detecting a read-write conflict for the data slot. A concurrency control mode of a data slot may be changed from a multi-version concurrency control mode to an optimistic concurrency control mode responsive to detecting that the data slot satisfies a low contention criterion.
Claims20
A method comprising:
- controlling a concurrency control mode of a data slot that stores a data value, wherein the concurrency control mode determines how a transaction is handled responsive to a read-write conflict, and controlling the concurrency control mode comprises:
- responsive to detecting a read-write conflict for the data slot, changing the concurrency control mode from an optimistic concurrency control mode to a multi-version concurrency control mode;
- and
- changing the concurrency control mode from the multi-version concurrency control mode to the optimistic concurrency control mode responsive to detecting that the data slot satisfies a low contention criterion.
A system comprising:
- a processor;
- and
- a set of memory resources storing:
- a data slot comprising:
- a committed in-place data value;
- and
- a mode indicator to indicate whether a concurrency control mode of the data slot is in an optimistic concurrency control mode that aborts a transaction upon detecting a read-write conflict, or a multi-version concurrency control mode that creates an additional version of the committed data value responsive to detecting the read-write conflict;
- and
- instructions in memory to be executed by a processor, the instructions when executed to:
- change the concurrency control mode from the optimistic concurrency control mode to the multi-version concurrency control mode responsive to detecting the read-write conflict for the data slot;
- and
- change the concurrency control mode from the multi-version concurrency control mode to the optimistic concurrency control mode responsive to detecting that the data slot satisfies a low contention criterion.
A non-transitory computer-readable medium comprising instructions executable by a processor to:
- detect a read-write conflict for a data slot;
- responsive to detecting the read-write conflict, change a concurrency control mode of the data slot from an optimistic concurrency control mode that aborts a transaction upon detecting a read-write conflict, to a multi-version concurrency control mode that creates an additional version of the stored data value;
- detect that a version chain locator of the data slot does not point to any additional version of the stored data value;
- responsive to detecting that the version chain locator does not point to any additional version of the stored data value, change the concurrency control mode from the multi-version concurrency control mode to the optimistic concurrency control mode.
Dependencies are inferred from the claim text.