Cache penetration and cache avalanche

1.Cache penetration:Query a data that does not exist. For example, to query an article table with a nonexistent ID, the database is accessed every time. If someone maliciously destroys the ID, it is likely to directly affect the database.

Solution: all the parameters that may be queried are stored in hash format. Check the parameters at the control layer first. If the parameters do not match, they are discarded.

2. cache failure:If the cache fails for a period of time, the pressure on the database is highlighted. There is no perfect solution, but we can analyze user behavior and try to make the failure time point evenly distributed.

 

-- See programmer magazine 2011.8 p48