Tom Lane wrote:
> Your sketch misses an important point: we want to know not only what
> each backend does, but when it does it. (For example, we'd want the
> test harness to be able to check that LOCK actually prevents another
> backend from making progress.) A brute-force way to do that would be
> to delay for some amount of time between issuing commands, so that we
> can be sure the backends have reached a quiescent state. Then, logging
> all the commands and responses serially into a single file would provide
> some idea of causal order. It could still be tricky though, eg if an
> unlock releases two other backends then their results could arrive in
> either order.
You could actually serialize all of the commands from one backend,
against multiple backends, using dblink.
Joe