* Fei Li (f...@suse.com) wrote: > Hi, > these two patches are to fix live migration issues. The first is > about multifd, and the second is to fix some error handling. > > But I have a question about using multifd migration. > In our current code, when multifd is used during migration, if there > is an error before the destination receives all new channels (I mean > multifd_recv_new_channel(ioc)), the destination does not exit but > keeps waiting (Hang in recvmsg() in qio_channel_socket_readv) until > the source exits. > > My question is about the state of the destination host if fails during > this period. I did a test, after applying [1/2] patch, if > multifd_new_send_channel_async() fails, the destination host hangs for > a while then later pops up a window saying > "'QEMU (...) [stopped]' is not responding. > You may choose to wait a short while for it to continue or force > the application to quit entirely." > But after closing the window by clicking, the qemu on the dest still > hangs there until I exclusively kill the qemu on the source.
That sounds like the main thread is blocked for some reason? But I don't normally use the window setup; if you try with -nographic and can see the HMP (or a QMP) monitor, can you see if the monitor still responds? If it doesn't then try and get a backtrace. The monitor really shouldn't block, so it would be interesting to see. Dave > The source host keeps running as expected, but I guess the hang > phenonmenon in the dest is not right. > Would someone kindly give some suggestions on this? Thanks a lot. > > > Fei Li (2): > migration: fix the multifd code > migration: fix some error handling > > migration/migration.c | 5 +---- > migration/postcopy-ram.c | 3 +++ > migration/ram.c | 33 +++++++++++++++++++++++---------- > migration/ram.h | 2 +- > 4 files changed, 28 insertions(+), 15 deletions(-) > > -- > 2.13.7 > -- Dr. David Alan Gilbert / dgilb...@redhat.com / Manchester, UK
