The server has waited for the short-term lock that prevents simultaneous CREATE TABLESPACE or DROP TABLESPACE commands. When wait events occur for lightweight locks, they are displayed by DRITA as well. A lightweight lock is used to protect a particular data structure in shared memory.Certain wait events can be due to the server process waiting for one of a group of related lightweight locks, which is referred to as a lightweight lock tranche. Individual lightweight lock tranches are not displayed by DRITA, but their summation is displayed by a single event named other lwlock acquire.For a list and description of lightweight locks displayed by DRITA, please see Section 28.2, The Statistics Collector in the PostgreSQL core documentation available at:Under Section 28.2.2. Viewing Statistics, the lightweight locks are listed in Table 28-4 wait_event Description where the Wait Event Type column designates LWLock.The following example displays lightweight locks ProcArrayLock, CLogControlLock, WALBufMappingLock, and XidGenLock.DRITA also displays wait events that occur that are related to certain Advanced Server product features.These Advanced Server feature specific wait events and the other lwlock acquire event are listed in the following table.