Class AcquireJobsCmd

    • Field Detail

      • numJobsToAcquire

        protected int numJobsToAcquire
    • Constructor Detail

      • AcquireJobsCmd

        public AcquireJobsCmd​(JobExecutor jobExecutor)
      • AcquireJobsCmd

        public AcquireJobsCmd​(JobExecutor jobExecutor,
                              int numJobsToAcquire)
    • Method Detail

      • isRetryable

        public boolean isRetryable()
        When CockroachDB is used, this command may be retried multiple times until it is successful, or the retries are exhausted. CockroachDB uses a stricter, SERIALIZABLE transaction isolation which ensures a serialized manner of transaction execution. A concurrent transaction that attempts to modify the same data as another transaction is required to abort, rollback and retry. This also makes our use-case of pessimistic locks redundant since we only use them as synchronization barriers, and not to lock actual data which would protect it from concurrent modifications. The AcquireJobs command only executes internal code, so we are certain that a retry of failed job locks will not impact user data, and may be performed multiple times.
        Specified by:
        isRetryable in interface Command<AcquiredJobs>
        true if the CrdbTransactionRetryInterceptor can make a transparent retry of this command upon failure with a CrdbTransactionRetryException (only used when running on CockroachDB).
      • getEntityType

        public Class<? extends DbEntity> getEntityType()
        Description copied from interface: OptimisticLockingListener
        The type of the entity for which this listener should be notified. If the implementation returns 'null', the listener is notified for all entity types.
        Specified by:
        getEntityType in interface OptimisticLockingListener
        the entity type for which the listener should be notified.