Introduced in
5aa2350.
Author: Peter Smith
Discussion: https://postgr.es/m/CAHut+PsuWz6_7aCmivNU5FahgQxDUTQtc3+__XnWkBzQcfn43w@mail.gmail.com
/*
* Setup a replication origin in the shared memory struct if it doesn't
- * already exists and cache access to the specific ReplicationSlot so the
+ * already exist and cache access to the specific ReplicationSlot so the
* array doesn't have to be searched when calling
* replorigin_session_advance().
*