ELASTIC stage v1.0

Pipelines v2.0

 

Purpose, Operands, Streams used, Usage notes, Examples, See also

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Syntax

 
>>__ELASTIC____________________________________________________________________________><

 

Purpose

 

Use the ELASTIC stage to prevent a stall in a multi-stream pipeline.

 

ELASTIC reads records from its primary input stream and writes them to its primary output stream; putting at least as many input records as necessary into a buffer to prevent a pipeline stall. ELASTIC reads input records whenever they become available and writes output records as they are consumed, while attempting to minimise the number of records in the buffer.

 

Operands

 

None.

 

Streams used

 

The following streams are used by the ELASTIC stage:

 

Stream

Action

 

 

Primary input stream

ELASTIC reads records from its primary input stream.

Primary output stream

ELASTIC writes the records it reads from its primary input stream to its primary output stream.

 

Usage notes

 

     1)

ELASTIC delays the records that it writes to a buffer.

 

     2)

If the ELASTIC stage discovers that its primary output stream is not connected, the ELASTIC stage ends.

 

     3)

ELASTIC can replace any BUFFER stage that is used for the prevention of a pipeline stall. However, use the BUFFER stage when you know that the complete file must be put in a buffer (for example, when another branch of the pipeline contains a SORT stage).

 

     4)

ELASTIC verifies that its secondary output stream is not connected and then begins execution.

 

Examples

 

Sorting a range of records

 

See also

 

Reference the following links for additional information:

 

BUFFER, FANIN, FANINANY

 

History of change

 

None.