any suggestion for completionTimeout value ?

Any suggestion for completionTimeout value? should I use it in my case? if
yes. what should be the proper value?

My scenario
JdbcAggregationRepository

aggregated message size will not bigger than 30KB

shutdownRoute="Defer" with timeout=5000 , should be long enough for
completing aggregating message before gracefully shutdown route

<bean id="shutdown"
class="org.apache.camel.impl.DefaultShutdownStrategy">
<property name="timeout" value="5000"/>
</bean>

<route id="aggregation_route" shutdownRoute="Defer">
<from uri="direct:aggregate" />
<aggregate strategyRef="output_agg" completionTimeout="3000">
<correlationExpression>
<simple>${header.myeventId}.${header.mysystem}</simple>
</correlationExpression>
<to uri="direct:aggregated"/>
</aggregate>
</route>