---
features:
  - |
    The new "cpu-pinning" element optimizes the amphora image for better
    vertical scaling. When an amphora flavor with multiple vCPUs is configured
    it will configure the kernel to isolate (isolcpus)
    all vCPUs except the first one.
    Furthermore, it uninstalls irqbalance and sets the IRQ affinity to the
    first CPU. That way the other CPUs are free to be used by HAProxy
    exclusively. A new customized TuneD profile applies some more tweaks
    for improving network latency.
    This new feature is disabled by default, but can be enabled by running
    `diskimage-create.sh` with the `-m` option or setting the
    `AMP_ENABLE_CPUPINNING` environment variable to 1 before running the script.
upgrade:
  - |
    Amphora vertical scaling optimizations require a new amphora image
    build with the optional CPU pinning feature enabled in order
    to become effective.