I was at Google when this became the standard more than a decade ago (https://www.usenix.org/sites/default/files/conference/protec...). For jobs where you had tens or hundreds of replicas, i.e. for services with lots of traffic, it made the rollout of new binaries in Borg much faster, especially if you were deploying to a cluster in Asia and your packages were built and stored in the US. Even in the US, this being before Firehose/Jupiter fabrics, network congestion had had noticeable impact.
MPM traffic was low priority, so for large enough binaries (and most of them were, because of static linking) you could easily see a Borg task spend seconds or even tens of seconds in "downloading" state if the borglet hadn't already seen and cached locally that version of the package.
It was about time this became available also for Docker and Kubernetes.
MPM traffic was low priority, so for large enough binaries (and most of them were, because of static linking) you could easily see a Borg task spend seconds or even tens of seconds in "downloading" state if the borglet hadn't already seen and cached locally that version of the package.
It was about time this became available also for Docker and Kubernetes.