The error original reported on https://issues.jboss.org/browse/MAISTRA-191 was never fixed.

Istio can get over 500GB of RAM usage with this rule
Here's a reproducer:

apiVersion: config.istio.io/v1alpha2
kind: rule
metadata:
generation: 1
name: stdiotcp
namespace: istio-system
spec:
actions:

• handler: handler.stdio
  instances:
• tcpaccesslog.logentry
  match: context.protocol == "tcp"

Can be reproduced customer reports it hapens in mixer 1.0.7