On 2011-10-10 11:02, Daniel P. Berrange wrote: > On Mon, Oct 10, 2011 at 08:52:08AM +0200, Jan Kiszka wrote: >> On 2011-10-10 04:21, Wen Congyang wrote: >>> At 10/09/2011 06:23 PM, Richard W.M. Jones Write: >>>> On Sun, Oct 09, 2011 at 10:49:57AM +0200, Jan Kiszka wrote: >>>>> As explained in the other replies: It is way more future-proof to use an >>>>> interface for this which was designed for it (remote gdb) instead of >>>>> artificially relaxing reasonable constraints of the migration mechanism >>>>> plus having to follow that format with the post-processing tool. >>>> >>>> Any interface that isn't "get this information off my production >>>> server *now*" so that I can get the server restarted, and send it to >>>> an expert to analyse -- is a poor interface, whether it was designed >>>> like that or not. Perhaps we don't have the right interface at all, >>>> but remote gdb is not it. >>> >>> What about the following idea? >>> >>> Introduce a new monitor command named dump, and this command accepts a >>> filename. >>> We can use almost all migration's code. We use this command to dump guest's >>> memory, so there is no need to check whether the guest has a unmigratable >>> device. >> >> I do not want to reject this proposal categorically, but I would like to >> see the gdb path fail /wrt essential requirements first. So far I don't >> see it would. > > GDB is often forbidden on production servers, so that path is > clearly not an option, unless we want libvirt to implement the > GDB remote RPC protocol itself which just sounds like a world > of hurt.
Run gdb with "set debug remote 1" and watch the communication, it is not that complex. But a dump command is probably simpler for those scenarios, I agree. Jan -- Siemens AG, Corporate Technology, CT T DE IT 1 Corporate Competence Center Embedded Linux
