The amount of buffer memory this port requires. There is a buffer server in each container. This is used to calculate total buffer server memory for container.
Also due to the nature of the application, if buffer server needs to use more RAM, from time to time, this number may
not be adhered to.
Input port attribute. Extend partitioning of an upstream operator w/o intermediate merge.
Can be used to form parallel partitions that span a group of operators.
Defined on input port to allow for stream to be shared with non-partitioned sinks.
If multiple ports of an operator have the setting, incoming streams must track back to
a common root partition, i.e. the operator join forks of the same origin.
Attribute of output port to specify how many partitions should be merged by a single unifier instance. If the
number of partitions exceeds the limit set, a cascading unifier plan will be created. For example, 4 partitions
with the limit set to 2 will result in 3 unifiers arranged in 2 levels. The setting can be used to cap the
network I/O or other resource requirement for each unifier container (depends on the specific functionality of
the unifier), enabling horizontal scale by overcoming the single unifier bottleneck.
Attribute to specify that the final unifier be always a single unifier. This is useful when in MxN partitioning
case there is a need to unify all the outputs of the M stage into a single unifier before sending the results to
the N stage. The attribute can be specified either on the output port or the input port, the output port being
the usual. The specification on the input port overrides that specified on the output port. This is useful in
cases when an output port is connected to multiple input ports and different unifier behavior is desired for
the inputs. In this case the default unifier behavior can be specified on the output port and individual
exceptions can be specified on the corresponding input ports.