[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] RE: [Patch][RFC] Support "xm dump" (is Re:[Xen-devel]Re:[Patch]Enable "sysrq c" handler for domU coredump)
Hi, Simon >I mean that if you want to crash a domain and collect a dump, you can do >'xm dump' followed by 'xm destroy' or 'xm reboot' -- there's no need to >add another command to do the combination. OK, I understand. >> >2. I don't see the point of the --noreboot option on 'xm dump' -- I >> >think this command >> > should simply live-dump the specified domain - as above you can >use >> >other commands >> > to cause the domain to restart afterwards. >> > >> Ordinary dump features have atomatically rebooting features. >> (e.g. diskdump, kdump, and so on) >> So I think this is necessary. > >xm dump foo >xm reboot foo OK. > >does the job nicely -- why complicate things by adding extra >options/commands > >> >> >3. There's no need to pause the domain to dump it - I actually wrote >a >> >little utility >> > to live dump a guest (based on xenconsoled and attached) and it >> seems >> >to work >> > quite nicely! This could easily be morphed into the 'xm dump' >> command >> >- it just >> > didn't occur to me at the time! >> > >> Your xendump command is dump feature without pause. >> In the case without pause, domain's memory is modified while dumping. >> I think both w/o and w pause are needed. > >Hmm... perhaps although I'm not convinced -- I understand that memory >can change during the dump and therefore there can be some >inconsistencies in the dump, HOWEVER, pausing the domain doesn't ensure >all the data structures are consistent either - it pretty much just >stops the VM wherever is happens to be so the memory can still be >inconsistent. > >I also think there is an issue with pausing -- unless I am mistaken, >pause requires code to run in the domain - if the domain is glued up >this cant run and the pause will hang (and lets face it, the usual >reason for dumping a domain is because something is wrong; definitely a >good idea to minimize the amount of work you expect from the domain in >this case). > >FWIW, my opinion is that it isn't necessary to pause. > I don't agree it. It is necessary to pause for dumping domU's core, because debugging is difficut with the unpause core. But I think we can resolve the issue with the following way. - If we want to get dump with pause 1. xm pause foo 2. xm dump foo 3. xm reboot foo (if want to reboot) - If we want to get live dump w/o pause 1. xm dump foo BTW, I try to make your xendump.c, but cannot compile it. Could you post the Makefile? I'd like to use your xendump. Best Regards, Akio Takebe _______________________________________________ Xen-devel mailing list Xen-devel@xxxxxxxxxxxxxxxxxxx http://lists.xensource.com/xen-devel
|
![]() |
Lists.xenproject.org is hosted with RackSpace, monitoring our |