Optimizing Cache Performance

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Some users might want to place the thumbnail cache on a separate, faster file system while keeping the actual photo files on large, slow bulk storage. This should result in faster access to the thumbnails.

To do this, we add a further volume (-v) parameter to the docker script so we use an external path (outside the container) for the cache files. You can get the internal path with photoprism config, or as a docker command in a running system (for Linux/BSD systems):

sudo docker exec photoprism photoprism config | grep cache-path

This should return a line such as:

cache-path            /home/photoprism/.cache/photoprism

for the internal path. We now know to add a line like

  -v <MYCACHE_FOLDER>:/home/photoprism/.cache/photoprism \

to the docker invocation, with your actual path to the cache folder replacing <MYCACHE_FOLDER>.

As an example, let's assume a ZFS filesystem with two pools ("volumes" in classical terminology): A pool tank in a raidz2 (RAID6) configuration based on hard drives that holds the original pictures, and a pool dozer in a mirrored (RAID1) configuration based on SSD or NVMe drives to store the thumbnails. Our docker script could be:

docker run -d \
  --name photoprism \
  -p 2342:2342 \
  -v /tank/photos/:/home/photoprism/Pictures/Originals \
  -v /dozer/cache/:/home/photoprism/.cache/photoprism \
  photoprism/photoprism:latest

In a case like this, you will probably also want to optimize the datasets ("file systems") tank/photos and dozer/cache further. For instance, the original photo files will call for a larger recordsize than the smaller cache files.