Decrease the time of cache living or move the cache storage to the Redis or text files.
Consult our user guide to learn how to switch to the text file.
The files will store caches of the page, the caches of the individual blocks will remain in core_cache.
To learn how to move the cache to Redis, please consult the following guide.
If the Redis is used the full page cache will be stored in it.
One more solution is to decrease the number of page combinations for Crawler:
It will help to reduce the number of combinations for each link when Crawler keeps your cache 'warm'.