Docker Layer Cacheing optimization: Pre-warming Docker Image Cache volumes
I'm about to release a new job to my team that builds a Docker image using Docker Layer Cacheing. If a few jobs are being run during a regular work day, the jobs should be mounting volumes with images available and these jobs should run quickly. However, as more developers start to run builds, many of them will not land on a volume that has these images available, causing their build times to increase (sometimes drastically).
It would be super convenient if some "pre-warming" or possibly copying occurred that would saturate enough volumes with image layers to handle the daily surge of parallel builds. I can imagine this happening totally under-the-hood, or potentially be configured in the circle config yaml when configuring the layer cacheing initially.