Custom properties
An estimation of how many items block the stream. This is used to determine the time the stream is not progressing anymore.
An estimation of how many iterations over items are executed. This is used to determine the CPU cost.
An estimation of how many items are stored in memory. This is used to determine the memory cost.
An estimation of the time to request items from sources. This is used to determine the I/O cost.
A mediator type that has an iterations parameter.