running 5.1-RELEASE with no procfs mounted (lockups?)
tlambert2 at mindspring.com
Fri Jul 18 01:53:09 PDT 2003
Pawel Jakub Dawidek wrote:
> +> truss Relies on the event model of procfs; there have been some
> +> initial patches and discussion of migrating truss to ptrace() but
> +> I don't think we have anything very usable yet. I'd be happy to
> +> be corrected on this. :-)
> Hmm, why to change this behaviour? Is there any functionality that
> ktrace(1) doesn't provide?
It can interactively run in another window, giving you realtime
updates on what's happening up to the point of a kernel crash.
With ktrace, you are relatively screwed.
Another good example is that it dump out information that ktrace
can't, because of where it synchronizes. Some people recently
have been seeing "EAGAIN" when they haven't expected it, with
the process exiting immediately after that, with no real clue
as to where in the code it's happening (e.g. which system call);
truss will show this, if run in another terminal window, but
ktrace will not (yes, I know it should; it doesn't. If you can't
reconcile this with how you think ktrace should work, then fix it).
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