Date: Fri, 18 Jul 2003 15:15:12 -0400 (EDT) From: John Baldwin <jhb@FreeBSD.org> To: Terry Lambert <tlambert2@mindspring.com> Cc: Robert Watson <rwatson@freebsd.org> Subject: Re: running 5.1-RELEASE with no procfs mounted (lockups?) Message-ID: <XFMail.20030718151512.jhb@FreeBSD.org> In-Reply-To: <3F17B3AE.1FD5CAC6@mindspring.com>
next in thread | previous in thread | raw e-mail | index | archive | help
On 18-Jul-2003 Terry Lambert wrote: > 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). Since ktrace logs all syscall entries and exits, it should seem that a kdump after the process had exited would show which syscall returned EAGAIN quite easily. -- John Baldwin <jhb@FreeBSD.org> <>< http://www.FreeBSD.org/~jhb/ "Power Users Use the Power to Serve!" - http://www.FreeBSD.org/
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?XFMail.20030718151512.jhb>