1. A method comprising: receiving a first request to perform a first operation that may be performed by a first code path within a server; detecting occurrence of a fault during performance of the first operation by the first code path; identifying a first entity involved in the first operation that experienced the fault; wherein the first entity is a first type of entity, wherein the first entity is one of: a SQL plan step, a SQL plan, a SQL statement, or a storage location targeted by an I/O request; in response to the first entity being involved in the first operation that experienced the fault, determining that quarantine criteria for the first code path has been satisfied relative to the first entity; in response to determining that quarantine criteria for the first code path has been satisfied relative to the first entity, storing data that indicates that the first entity is quarantined relative to the first code path while continuing to allow the first code path to be executed for operations involving other entities of the first type of entity; after storing data that indicates that the first entity is quarantined relative to the first code path, receiving a second request to perform a second operation; in response to the second request, determining whether the first entity is involved in the second operation; in response to determining that the first entity is involved in the second operation and that the first entity is quarantined relative to the first code path, responding to the second request without using the first code path; wherein the method is performed by one or more computing devices.