A method is described for parallel processing of sequence operations, in
which contention for the sequence operation is reduced among multiple
parallel processes. Contention is reduced by caching sequence values
locally for each parallel process. Each process accesses the sequence
operation, or an instance level cache of sequence values, in a batched
manner, thereby returning a block of unique sequence values instead of a
single sequence value. The block of sequence values, or at least
information that indicates a range of sequence values that define the
block, is then cached locally in association with a given process of the
multiple processes. Hence, future requests for sequence values from the
given process are serviced from the local cache, rather than having to
access the sequence operation and risk contention for the operation with
other processes.