hmm, with only the dump snapshot it still hangs. dmesg is similar:
[147928.992344] libceph: get_reply osd3 tid 638001 data 933888 > preallocated 131072, skipping
USER PID %CPU %MEM VSZ RSS TTY STAT START TIME COMMAND
root 11148 0.0 0.0 21984 1240 ? D 20:47...