Cloudimage caches all your origin images and their transformations (resizes, crops, watermarks, ...) on its resizing infrastructure for faster delivery to the CDN nodes (POPs) - more details on the Cloudimage infrastructure here. This is your token's Image Cache, which is measured in GB and is the sum of all origin images and their transformations.
Unlike CDN traffic which is reset on a monthly basis, the Image Cache is cumulative and grows (when you process new images with Cloudimage) or shrinks (when you invalidate your images via the Cloudimage Admin Console or Invalidation API + automatically, see Note 1 below) over time.
Billing is based on the Image Cache used on the last day of the month. If your Image Cache is above the allowance, we will charge you for overuse based on your plan's overuse cost per GB at the last day of the month.
Note 1: images which are not regularly called by the CDN (called inactive images) are automatically flushed from your token's Image Cache by Cloudimage's cache-cleaning algorithm, in order to keep its size as optimal as possible and avoid overuse charges.
Note 2: images flushed from your Image Cache are still available in the CDN cache and delivered to your end user until you invalidate them from your Admin Console or per API. In case an inactive image is flushed from your Image Cache and called at a later point in time, Cloudimage will re-download it from your origin server, hence there is no risk of data loss.
Let's say you process a first set of 10 GB (origins + transformations) of images (Set A) through Cloudimage on January 10th. On January 15th you process 15 GB of new images (Set B) through Cloudimage. At the end of the day on January 15th, your Image Cache will be 10 + 15 = 25 GB.
Few scenarios are then possible (in both Scenarios assume that all images from Set B are active):
- Scenario 1: if none of the images from Set A are called within a certain amount of time, as defined by our cache optimization algorithms, they will be flushed from your Image Cache (inactive images), which size will shrink to 25 - 10 = 15 GB.
- Scenario 2: if only certain images from Set A, amounting to 5 GB of origin image size + transformations are called within a certain amount of time, the inactive images will be flushed from your Image Cache, which size will shrink to 25 - 5 = 20 GB.
How can I control my Image Cache?
You have two options to reduce your Image Cache:
- Invalidate images from the Cloudimage Admin Console or Invalidation API. Keep in mind that invalidating your entire cache might overload your origin server and lead to slow image performance on your web applications as Cloudimage will have to re-download the entire image library from your origin again.
- Contact us for a custom configuration of your Image Cache, for example: flush images older than N days (ROCKET+ plans).