> There are indeed occasions where you need a proper rr-like trace, but what fraction of bugs fall into that category.
Good question. I guess it depends on what you mean by "need".
If you mean "for what fraction of bugs will a developer be unable to figure out the bug, given only the state where the error surfaced, but given unlimited time", I don't know. Most developers I've worked with either have rr recordings available or they do the work to reproduce the bug locally so they can work backwards to the root cause by rerunning the test, so their experiences don't reflect those constraints.
If you mean "for what fraction of bugs is it valuable to have an rr recording", I think the answer is very clearly "almost all". Many rr users, some on this very HN thread, will testify that debugging with rr is almost always better than debugging with gdb alone, whether or not they are able to reproduce the bug on-demand for debugging with gdb.
Good question. I guess it depends on what you mean by "need".
If you mean "for what fraction of bugs will a developer be unable to figure out the bug, given only the state where the error surfaced, but given unlimited time", I don't know. Most developers I've worked with either have rr recordings available or they do the work to reproduce the bug locally so they can work backwards to the root cause by rerunning the test, so their experiences don't reflect those constraints.
If you mean "for what fraction of bugs is it valuable to have an rr recording", I think the answer is very clearly "almost all". Many rr users, some on this very HN thread, will testify that debugging with rr is almost always better than debugging with gdb alone, whether or not they are able to reproduce the bug on-demand for debugging with gdb.