Based on the feedback, this seems to be a good idea, approximately. Coleen would have sponsored, but she's going on vacation. Anyone else feel like sponsoring?
Jeremy On Wed, Jul 22, 2015 at 11:22 AM, Jeremy Manson <jeremyman...@google.com> wrote: > Hey folks, > > os::current_thread_id on Linux now maps to pthread_self. The problem with > pthread_self is that it only makes sense in the context of the running > process. When it is written out to the log (as it is in several places), > there really isn't a way (AFAICT) for the user to map it back to anything > useful. > > As it happens, that value is mostly used to write to the log. The places > where it doesn't do so don't seem to need to use pthread_self for any > particular reason. > > Meanwhile, the SIGQUIT stack dump > uses java_thread->osthread()->thread_id() as the nid. On Linux, that maps > back to os::Linux::gettid(), whish is also what gets exposed in /proc. > That makes it much easier to see what threads might be doing the log write. > > Would it be okay to change os::current_thread_id to point > to os::Linux::gettid()? That way, it can be mapped back to the output of a > SIGQUIT dump. > > The downside of gettid() is that it is only available on Linux>2.4.11, but > that dates from 2001. If we really still want to support it, we could > check for that. > > Thoughts? > > Jeremy >
