Achieve near-zero downtime during OpenStack upgrades with Atmosphere’s new "ovsinit" utility and AVX-512-optimized OVS builds for faster, more efficient networking.
Upgrading OpenStack often comes with one unavoidable risk: temporary data plane interruptions. In Atmosphere, we’ve already solved a major part of this challenge by decoupling Open vSwitch (OVS) image builds from platform upgrades — eliminating unnecessary OVS restarts.
Now, we’re taking that even further. Atmosphere introduces two key improvements that make OpenStack networking faster and more resilient than ever:
- Open vSwitch builds with AVX-512 optimization for next-generation CPU performance.
- A new component,
ovsinit, purpose-built to minimize data plane downtime during restarts.
Accelerating OpenStack Networking with AVX-512
Atmosphere’s Open vSwitch images are now compiled with AVX-512 support, unlocking advanced CPU instructions available on modern Intel processors.
That translates directly into higher throughput and efficiency for both kernel and DPDK datapaths — improving packet processing, reducing CPU load, and delivering smoother performance under heavy workloads.
These enhancements require no configuration changes — they’re automatic for any compatible hardware, bringing performance improvements out-of-the-box.
Introducing ovsinit: Minimal Downtime, Maximum Control
Even with previous optimizations, traditional Kubernetes behavior still caused short data plane interruptions when Open vSwitch daemons restarted. Kubernetes typically stops an old pod before starting a new one — meaning if image pulls are slow or startup takes time, networking can go dark for several seconds.
ovsinit fixes that by rethinking how Open vSwitch daemons are restarted inside Kubernetes.
When used as the container entry point, ovsinit:
- Detects if an Open vSwitch process (like
ovs-vswitchd or ovsdb-server) is already running. - Gracefully stops it using
appctl exit. - Waits for a clean shutdown.
- Uses
syscall.Exec to start the new process in-place — preserving its PID and data plane state.
