# The Parallelization tab Available in... * Big Data * Big Data Platform * Cloud API Services Platform * Cloud Big Data * Cloud Big Data Platform * Cloud Data Fabric * Cloud Data Management Platform * Data Fabric * Data Management Platform * Data Services Platform * MDM Platform * Real-Time Big Data Platform The Parallelization tab is available as one of the settings tab you can use to configure a Row connection. ![](https://help.qlik.com/talend/en-US/studio-user-guide/Resources/images/tis_parallelization.png) You define the parallelization properties on your row connections according to the following table. | Field/Option | Description | | --- | --- | | Partition row | Select this option when you need to partition the input records
into a specific number of threads.

Information noteNote:

It is not available to the last row connection of the
flow. | | Departition row | Select this option when you need to regroup the outputs of the
processed parallel threads.

Information noteNote:

It is not available to the first row connection of the
flow. | | Repartition row | Select this option when you need to partition the input threads
into a specific number of threads and regroup the outputs of the
processed parallel threads.

Information noteNote:

It is not available to the first or the last row connection
of the flow. | | None | Default option. Select this option when you do not want to take
any action on the input records. | | Merge sort partitions | Select this check box to implement the Mergesort algorithm to
ensure the consistency of data.

This check box appears when you select the Departition
row or Repartition row
option. | | Number of Child Threads | Type in the number of threads into which you want to split the
input records.

This field appears when you select the Partition
row or Departition row
option. | | Buffer Size | Type in the number of rows to cache for each of the threads
generated.

This field does not appear if you select the
None option. | | Use a key hash for partitions | Select this check box to use the hash mode for dispatching the
input records, which will ensure the records meeting the same
criteria are dispatched to the same threads. Otherwise, the
dispatch mode is Round-robin.

This check box appears if you select the Partition
row or Repartition row
option.

In the Key Columns table that appears
after you select the check box, set the columns on which you
want to use the hash mode. |