In January I blogged about important Query Store fixes that were available in current CUs. Check my January post for fixes through SQL Server 2016 SP2 CU5 and SQL Server 2017 CU13.
I’m using this post to track Query Store fixes/enhancements since those releases, so you can find updates here as additional CUs are released throughout the summer.
SQL Server 2016 SP2 CU7
I definitely recommend that you update to this CU if you are using Query Store with SQL Server 2016 SP2, especially if you have an ad hoc or mixed workload.
Remember that runtime statistics and some query information is stored in-memory, and this CU addresses an issue with cleanup of the runtime statistics, based on the CLEANUP_POLICY and MAX_STORAGE_SIZE_MB.
I have seen issues where the space used for Query Store exceeds the MAX_STORAGE_SIZE_MB settings, and this CU should help address that behavior. Again, it’s important to make sure your Query Store is sized appropriately, based on the type of workload you have (ad hoc will require more space) and how long you want to keep your data. While it’s nice to keep 30 days of data, in some scenarios that doesn’t fit within the 10GB “ideal” size for Query Store.
I don’t see this fix in a 2017 CU.