Nexmark Query 3 produces inconsistent output size on Direct runner

It seems that Direct runner is producing inconsitent outputs for Nexmark Query 3. All other runners produce constant output and even the SQL based queries on Direct runner do, so worth investigating.

This happens in both batch and streaming.

http://104.154.241.245/d/x51DT0OMk/nexmark-output-size?orgId=1&from=now-6M&to=now&var-processingType=batch&var-ID=3&var-runner=DirectRunner