Hot partition on the loyalty table

Incident drill · Advanced

What is happening

Alert: loyalty API p95 above 3 s and errors at 20% on double-points day.

Every sale adds points to the member’s row, and every till asks for the balance before and after the sale. All of it goes to one database primary, which is at 100% CPU.

Fix it for the rest of the day: the points must still be written to the primary.

You have 4 changes and 8 minutes. A change is adding or removing a part or a connection, or changing a part’s settings. Fewer changes and less time score higher.