On Fri, Jul 29, 2016 at 9:55 AM, Josh Durgin <jdurgin@xxxxxxxxxx> wrote: > On 07/29/2016 09:40 AM, Ken Dreyer wrote: >> >> daemon-helper predates a lot of things in Ceph, and the further we go >> into systemd-land with things like unprivilged daemons, SELinux, and >> cgroups, the further Teuthology diverges from what our users do. To >> remedy this, I want to retire daemon-helper and have Teuthology tests >> use the normal init system, particularly now that our main supported >> distros are unified around systemd. >> >> From what I understand, we use daemon-helper in Teuthology to: >> >> 1) start a daemon and eventually stop it with either SIGTERM or >> SIGKILL, depending on whether the Teuthology task has enabled the >> coverage or valgrind options, >> >> 2) send data via STDIN >> >> 3) print some messages when the child crashes >> >> I think we could run the services using the systemd unit files and >> still accomplish #1 and #3. >> >> For #2 (communicating to the daemons via STDIN), how could we >> accomplish this? What sort of things are we writing to the daemons' >> STDIN? I'm having trouble finding examples in ceph-qa-suite.git. > > > We're not using it to write data to the daemons, but as a way to kill them > automatically if our ssh connection dies. > > With fast reimaging in the works, this will be irrelevant. Even now, > it's not really useful for the usual scheduled jobs where the nodes are > rebooted on failure. So I wouldn't worry about (2). I think we also use this to kill processes by closing stdin on the teuthology process side. Some quick grepping suggests we have ~21 call sites and they're largely not in the tracker; I don't imagine they'll be too hard to replace but it might be a little awkward in some places. -Greg -- To unsubscribe from this list: send the line "unsubscribe ceph-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
