As I help lead the Istio User Experience Working Group, I can confirm that there's a cost to telemetry gathered and sent to Mixer and that tuning the type and amount of telemetry sent can can a dramatic impact on the overhead involved in using the service mesh.<p>In general, the question of overhead is concern that most adopters of a service mesh ask. Akin to deploying an application performance monitoring agent to your server or an SNMP poller to your network, there's a price to be paid for the ability to observe and control your workloads. Illuminating this cost, understanding and controlling this cost is the goal of an open source project, Meshery (<a href="https://layer5.io/meshery" rel="nofollow">https://layer5.io/meshery</a>). Meshery acts as a performance benchmark for multi-mesh performance comparison (an apples-to-apples comparison across different service meshes).<p>Note that it's not necessary for each sidecar proxy call to validate every network call with Mixer. Many of these validations are locally cached in the sidecar proxy and do not involve Mixer.