ReferenceGlossary
Cache stampede
Many requests miss the same cached data at the same moment, for example after a cache restart or an expiry, and all of them go to the database together. The extra load can slow the database so much that the cache never refills.
Data
In Quorum#
In the Cache stampede Incident a Cache restarts empty, and every miss goes to the Database at once. While the Database is 90% busy or more, refills time out and the Cache stays cold. Stampede protection lets a cold Cache send on only 25% of its extra misses. Cache warming brings it back 80% warm after a restart.
Read next#
Thundering herd, Cache warming, Cache-aside, Metastable failure