Pipeline blocking from output plugins

We keep running into an issue where all logstash processing gets halted if one of our output plugins runs into an issue. For example, if our PagerDuty or Graphite outputs are not able to function correctly due to a connectivity issue, the logstash pipeline fills up and all processing grinds to a halt.

I understand this is due to the way the logstash pipeline was designed. I think I've seen talk of possibly splitting up the pipeline to avoid this issue. Does anyone know if that is on the roadmap for an upcoming release? Or does anyone have any workarounds for this problem?

Thanks