CNCF-hosted Co-located Events Europe 2025

In an Istio service mesh, all workloads have to be continuously kept up to date with the latest cluster configuration. However, only few or no workloads communicate with every other workload. Keeping superfluous information up to date across the whole cluster creates unnecessary load and increases the cluster convergence time, which results in errors.

One way to optimise this behaviour is by leveraging the Istio Sidecar resource. Workloads specify egress hosts for the services they need to communicate with, updates are then sent only when an egress host IP address changes.

This talk will cover GetYourGuide’s adoption of the Istio Sidecar resource - trade offs of the implementation; rolling out high criticality configuration changes in a live cluster.

We will showcase how we reduced cluster convergence by 10x and eliminated all lag related networking errors by rolling out the Istio Sidecar resource across ~300 services without any incidents and with very little time investment.