Per discussion on this very page, in the headlined article, and in the mailing list discussion it references, PostgreSQL is not in that category. It has lots of static storage duration variables, which do not necessarily have external linkage.
Robert Haas pointed out in one message that an implementation pattern was to use things like file-scope static storage duration variables to provide session-local state for individual components. This is why they've been arguing against a single giant structure declared in "session.h" as an approach, as it requires every future addition to session state to touch the central core of the entire program.
They want to keep the advantage of the fact that these variables are in fact not global. They are local; and the problem is rather that they have static storage duration and are not per-thread, and thus are not per-session in a thread-per-session model.
Robert Haas pointed out in one message that an implementation pattern was to use things like file-scope static storage duration variables to provide session-local state for individual components. This is why they've been arguing against a single giant structure declared in "session.h" as an approach, as it requires every future addition to session state to touch the central core of the entire program.
They want to keep the advantage of the fact that these variables are in fact not global. They are local; and the problem is rather that they have static storage duration and are not per-thread, and thus are not per-session in a thread-per-session model.