Re: kern/104406: [ufs] Processes get stuck in "ufs" state underpersistent CPU load
Rainer Hurling wrote: Looking into PR kern/104406 it seems, that this describes exactly what I am experiencing on three of my systems over the last weeks. They are running FreeBSD 8.0-CURRENT (known as 7.0-CURRENT not long ago ;-) ). Actually it sounds nothing like it at all ;) On these machines I often observe hangings, sometimes only a few seconds, on other times 20-30 seconds before input/output is back. This seems to happen when more extensive disk usage is needed (portupgrade, buildworld, browsing complicated websites etc.). During the hang even xterm is not responding any more, other (diskless) applications like xclock keep to continue. I have no panics, only UFS (and MSDOSFS) are mounted, no NTFS. About two months ago none of my systems showed these hangings. Is your system swapping? This is the usual cause of pauses during high application (actually memory) load. Kris ___ freebsd-stable@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-stable To unsubscribe, send any mail to "[EMAIL PROTECTED]"
Re: kern/104406: [ufs] Processes get stuck in "ufs" state underpersistent CPU load
* Oleg Derevenetz <[EMAIL PROTECTED]> [071020 09:58] wrote: > > > Can anyone take a look on PR kern/104406 ? I got repeatable hang > situation, > > > but I can't obtain a kernel dump to get result of all show commands from > > > here: > > > > > > > http://www.freebsd.org/doc/en_US.ISO8859-1/books/developers-handbook/kerneldebug-deadlocks.html > > > > > > After my break to debugger using Ctrl+Alt+Esc sequence and entering a > > > "panic" command kernel does not wrote a kernel dump but seems to hang. > Can > > > anyone describe how to obtain a kernel dump in this situation, or at > least > > > say - which output of show commands need in first place to debug this ? > > > Output of all suggested commands is huge and I afraid of making mistake > > > when carrying this output from screen to list of paper and back :-) > > > > Oleg, one thing you can do to make this less painful is to > > run your machine's console over serial port. > > > > First get a crossover serial cable, make sure it works from one > > box to another, it should be easy to run "tip com1" on both > > boxes to ensure that it works. > > > > Then you just need to add console=comconsole to /boot/loader.conf > > and your box's console should come over serial. > > > > Then on the machine watching the console, you can just do this: > > > > % script > > Script started, output file is typescript > > % tip com1 > > ...do ddb stuff now... > > ...stop tip > > % exit > > > > now you should have everything logged into a file called "typescript" > > should save you a big headache. > > Thanks, I'll try it in the monday morning. > > > As far as getting a dump from ddb, try this: > > > > ddb> call doadump > > > > I'm completely at a loss why this isn't a base ddb command "dump" > > but whatever... :) > > Unfortunately, this doesn't work too. I called duty personnel in this > datacenter and asked them to do this, and person on duty tells me that after > he enters this command something like that arrives on monitor: > > db> call doadump > Dumping 3072 MB > > Dump aborted error I/O > Dump failed. (Error 5) Hmnmm, that seems like you might be having a hardware problem, what disk device do you have? Have you also enabled kernel dumps via /etc/rc.conf:dumpdev= ? -- - Alfred Perlstein ___ freebsd-stable@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-stable To unsubscribe, send any mail to "[EMAIL PROTECTED]"
Re: kern/104406: [ufs] Processes get stuck in "ufs" state underpersistent CPU load
> > Can anyone take a look on PR kern/104406 ? I got repeatable hang situation, > > but I can't obtain a kernel dump to get result of all show commands from > > here: > > > > http://www.freebsd.org/doc/en_US.ISO8859-1/books/developers-handbook/kerneldebug-deadlocks.html > > > > After my break to debugger using Ctrl+Alt+Esc sequence and entering a > > "panic" command kernel does not wrote a kernel dump but seems to hang. Can > > anyone describe how to obtain a kernel dump in this situation, or at least > > say - which output of show commands need in first place to debug this ? > > Output of all suggested commands is huge and I afraid of making mistake > > when carrying this output from screen to list of paper and back :-) > > Oleg, one thing you can do to make this less painful is to > run your machine's console over serial port. > > First get a crossover serial cable, make sure it works from one > box to another, it should be easy to run "tip com1" on both > boxes to ensure that it works. > > Then you just need to add console=comconsole to /boot/loader.conf > and your box's console should come over serial. > > Then on the machine watching the console, you can just do this: > > % script > Script started, output file is typescript > % tip com1 > ...do ddb stuff now... > ...stop tip > % exit > > now you should have everything logged into a file called "typescript" > should save you a big headache. Thanks, I'll try it in the monday morning. > As far as getting a dump from ddb, try this: > > ddb> call doadump > > I'm completely at a loss why this isn't a base ddb command "dump" > but whatever... :) Unfortunately, this doesn't work too. I called duty personnel in this datacenter and asked them to do this, and person on duty tells me that after he enters this command something like that arrives on monitor: db> call doadump Dumping 3072 MB Dump aborted error I/O Dump failed. (Error 5) -- Oleg Derevenetz <[EMAIL PROTECTED]> OOD3-RIPE Phone: +7 4732 539880 Fax: +7 4732 531415 http://www.vsi.ru CenterTelecom Voronezh ISPhttp://isp.vsi.ru ___ freebsd-stable@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-stable To unsubscribe, send any mail to "[EMAIL PROTECTED]"
Re: kern/104406: [ufs] Processes get stuck in "ufs" state underpersistent CPU load
Looking into PR kern/104406 it seems, that this describes exactly what I am experiencing on three of my systems over the last weeks. They are running FreeBSD 8.0-CURRENT (known as 7.0-CURRENT not long ago ;-) ). On these machines I often observe hangings, sometimes only a few seconds, on other times 20-30 seconds before input/output is back. This seems to happen when more extensive disk usage is needed (portupgrade, buildworld, browsing complicated websites etc.). During the hang even xterm is not responding any more, other (diskless) applications like xclock keep to continue. I have no panics, only UFS (and MSDOSFS) are mounted, no NTFS. About two months ago none of my systems showed these hangings. I know that this 'hanging' behaviour has been described several times in the near past on STABLE and CURRENT lists. But mostly the context was different. In discussions beared on these hangings it seems people are looking for misbehaviour of the scheduler (namely ULE), linux emulation, java runtime environment or firefox. At my point of view it has more likely to do with UFS-locking under high cpu load or something around it. I have barely skills with programming and debuging, but if there are any activities on this topic in the background, what can we do to help? Sincerely, Rainer Hurling Oleg Derevenetz schrieb: Can anyone take a look on PR kern/104406 ? I got repeatable hang situation, but I can't obtain a kernel dump to get result of all show commands from here: http://www.freebsd.org/doc/en_US.ISO8859-1/books/developers-handbook/kerneldebug-deadlocks.html After my break to debugger using Ctrl+Alt+Esc sequence and entering a "panic" command kernel does not wrote a kernel dump but seems to hang. Can anyone describe how to obtain a kernel dump in this situation, or at least say - which output of show commands need in first place to debug this ? Output of all suggested commands is huge and I afraid of making mistake when carrying this output from screen to list of paper and back :-) This very easy to reproduce [ufs] uninterruptable deadlock for both of RELENG_6 and RELENG_7. Look at this PR: http://www.freebsd.org/cgi/query-pr.cgi?pr=kern/107439 The PR is closed but the problem is still here with 7.0-PRERELEASE and, perhaps, CURRENT. This is probably another bug because: 1. I built kernel with INVARIANTS as described in on "Debugging Deadlocks" page of FreeBSD Developers' Handbook and got no panic, but only deadlock; 2. I have no NTFS filesystem at all and just do a copy of file(s) from FTP to local UFS using mc. In this PR panic occured when NTFS mounted r/w (and NOT occured when the same NTFS mounted r/o). -- Oleg Derevenetz <[EMAIL PROTECTED]> OOD3-RIPE Phone: +7 4732 539880 Fax: +7 4732 531415 http://www.vsi.ru CenterTelecom Voronezh ISPhttp://isp.vsi.ru ___ freebsd-stable@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-stable To unsubscribe, send any mail to "[EMAIL PROTECTED]"
Re: kern/104406: [ufs] Processes get stuck in "ufs" state underpersistent CPU load
On Sat, Oct 20, 2007 at 12:44:46PM +0400, Oleg Derevenetz wrote: > This is probably another bug because: [skip] Then there should be another one distinct bug as God likes the Trinity. Eugene ___ freebsd-stable@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-stable To unsubscribe, send any mail to "[EMAIL PROTECTED]"
Re: kern/104406: [ufs] Processes get stuck in "ufs" state underpersistent CPU load
> > > Can anyone take a look on PR kern/104406 ? I got repeatable hang situation, > > > but I can't obtain a kernel dump to get result of all show commands from > > > here: > > > > > > http://www.freebsd.org/doc/en_US.ISO8859-1/books/developers-handbook/kerneldebug-deadlocks.html > > > > > > After my break to debugger using Ctrl+Alt+Esc sequence and entering a > > > "panic" command kernel does not wrote a kernel dump but seems to hang. Can > > > anyone describe how to obtain a kernel dump in this situation, or at least > > > say - which output of show commands need in first place to debug this ? > > > Output of all suggested commands is huge and I afraid of making mistake > > > when carrying this output from screen to list of paper and back :-) > > This very easy to reproduce [ufs] uninterruptable deadlock > for both of RELENG_6 and RELENG_7. Look at this PR: > http://www.freebsd.org/cgi/query-pr.cgi?pr=kern/107439 > > The PR is closed but the problem is still here with 7.0-PRERELEASE > and, perhaps, CURRENT. This is probably another bug because: 1. I built kernel with INVARIANTS as described in on "Debugging Deadlocks" page of FreeBSD Developers' Handbook and got no panic, but only deadlock; 2. I have no NTFS filesystem at all and just do a copy of file(s) from FTP to local UFS using mc. In this PR panic occured when NTFS mounted r/w (and NOT occured when the same NTFS mounted r/o). -- Oleg Derevenetz <[EMAIL PROTECTED]> OOD3-RIPE Phone: +7 4732 539880 Fax: +7 4732 531415 http://www.vsi.ru CenterTelecom Voronezh ISPhttp://isp.vsi.ru ___ freebsd-stable@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-stable To unsubscribe, send any mail to "[EMAIL PROTECTED]"
