Kernel-side: ktrace

• tracing a process should trace all its threads

• need to record and (optionally) display the thread id in the ktrace output

  • always had to use ktrace -di when tracing threaded procs

• most of the work was in improving kdump output and fixing unrelated issues

  • what credentials should be used when writing ktrace output?

  • what process file-size limit?

• thank you to the clever cookie on the FreeBSD project that came up with dumping of structure by ktrace

• very useful for debugging