# Siren Platform User Guide

From  ManagementData Model., click Edit () to open the advanced settings for each relation. Here you can set the maximum time spent by each join task for that relation in milliseconds. After the timeout has expired, the task passes the documents accumulated at that point on to the next task.

This is a per-task time limit and as each join contains several tasks, the overall response to the request can be a number of multiples of the joinTaskTimeout.

As a semi-join, these documents will be filtered based on the presence of a non-empty value for the join field in the other index pattern in the relation.

The index pattern in question is then filtered by the values returned.

Setting the limit here to -1 here sets the limit to the default siren:joinTaskTimeout set in the Advanced Settings and setting the limit to 0 here removes the limit entirely.

##### Join type

Siren Federate provides two types of join algorithms. The plugin tries to pick the best algorithm for a given join automatically. However, you can force the selection by choosing one of the available options: