es and output buffers. Mixer thus acts as a highly-scaled and highly-available second-level cache for the sidecars.</p><p>Mixer’s expected availability is considerably higher than most infrastructure backends (those often have availability of perhaps 99.9%). Its local caches and buffers help mask infrastructure backend failures by being able to continue operating even when a backend has become unresponsive.</p><h2 id="mixer-latency-slasher">Mixer: Latency slasher</h2><p>As we explained above, the Istio si