Failing to open process ID causes a process to spin

If a disk issue causes a process to fail to open its process ID file, then the process will die. fdbmonitor will then repeatedly restart it. An alternative here could be to have a process to remain alive with no roles, which is what happens in the case that an IO error happens later in the process’s lifetime.

Start by tracing how the process opens its process ID file and how fdbmonitor handles that failure and restarts the process. Compare this path with the later-lifetime IO error behavior described in the issue; done means a persistent PID-file open failure no longer causes repeated restarts, or the intended no-role state is clearly implemented.

Written by the indexing model from the issue text.