When multiple threads write to a single directory, the mapping might encounter a bottleneck due to input/output (I/O) contention. An I/O contention can occur when threads write data to the file system at the same time.

When you configure multiple directories, the Data Integration Service determines the output directory for each thread in a round-robin fashion. For example, you configure a flat file data object to use directoryA and directoryB as target directories. If the Data Integration Service uses four threads to write to the file target, the first and third writer threads write target files to directoryA. The second and fourth writer threads write target files to directoryB.

If the Data Integration Service does not use multiple threads to write to the target, the service writes the output file to the first listed directory.

Configure the output file directories in the

Advanced

properties for the flat file data object. Find the

Output File Directory

property in the

Runtime: Write

section. By default, the property is configured to use the system parameter value defined for the Data Integration Service. Use the default TargetDir system parameter value if an administrator entered multiple directories separated by semicolons for the

Target Directory

property for the Data Integration Service.

You can enter a different value to configure multiple output file directories specific to the flat file data object. Enter multiple directories separated by semicolons for the property or for the user-defined parameter assigned to the property.