A delayed to clear cache.
An implementation of a cache to be used selectively on Views and Blocks so that they don't get cleared when a Drupal Clear cache is issued or other triggers that would other wise immediate clear the cache and cause a regeneration of the data/content.
The concept behind this cache is that by choosing which views and/or blocks are too heavy to generate (causing the server performance to go down on high traffic sites), allowing them to be generated some time after and not at the same time, doing a redistribution of the work during time.
At some events the cache is cleared and therefore all data needs to be generated and processed again, if this happens for some heavy processes on a high traffic site you may end up running several heavy process at the same time plus all the small process and you may bring the server down temporary, similar to what happens with a DOS attack.
If we can delay the most heavy parts to be processed after all other caches are ready and meanwhile we use "old" caches for those parts until we get those processed again it would allow to redistribute the processing during time and not all at the same time.