On Tue, Jun 20, 2017 at 12:19:01PM +0200, Gaëtan Rivet wrote: > On Tue, Jun 20, 2017 at 11:58:54AM +0200, Thomas Monjalon wrote: > > 20/06/2017 11:22, Bruce Richardson: > > > On Mon, Jun 19, 2017 at 11:12:53PM +0200, Thomas Monjalon wrote: > > > > 15/06/2017 14:05, De Lara Guarch, Pablo: > > > > > > Add parameter to start forwarding sending first > > > > > > a burst of packets, which is useful when testing > > > > > > a loopback connection. > > > > > > > > > > > > This was already implemented as an internal command, > > > > > > but adding it as a parameter is interesting, as it > > > > > > allows the user to test a loopback connection without > > > > > > entering in the internal command line. > > > > > > > > > > > > Signed-off-by: Pablo de Lara <pablo.de.lara.gua...@intel.com> > > > > > > --- > > > > > > --- a/doc/guides/testpmd_app_ug/run_app.rst > > > > > > +++ b/doc/guides/testpmd_app_ug/run_app.rst > > > > > > @@ -188,6 +188,14 @@ The commandline options are: > > > > > > > > > > > > Start forwarding on initialization. > > > > > > > > > > > > +* ``--tx-first`` > > > > > > + > > > > > > + Start forwarding, after sending a burst of packets first. > > > > > > + > > > > > > +.. Note:: > > > > > > + > > > > > > + This flag should be only used in non-interactive mode. > > > > > > > > I don't really understand the benefit of this option. > > > > Why is it better than > > > > echo start tx_first | testpmd -i > > > > ? > > > > > > The one big difference I see is normal vs abnormal termination. With the > > > echo command you suggest, the only way to terminate testpmd is to kill > > > it via signal. With the extra cmdline option, it will cleanly exit via > > > enter as with non-interactive mode right now. Not a huge difference, but > > > I think having the extra argument to enable tx-first is useful. > > Side note, one can: > > (trap 'echo quit' SIGUSR1; echo 'start'; while true; do sleep 1; done) > |testpmd -i & > > and issue a SIGUSR1 to the subshell to cleanly quit testpmd. > Or: > > (trap 'echo show port stats all' SIGUSR1; \ > trap 'echo quit' SIGUSR2; \ > echo 'start'; \ > while true; do :; done) |\ > testpmd -i & > > It's a little contrived, but it does the job and is easy enough to put > in scripts. > Or we can just put in a --tx-first flag and save the user the pain of doing multi-line bash commands. Usability is a constant complaint about DPDK that we hear e.g. at userspace every year, so we need to stop assuming everyone looking to play with DPDK is a shell power-user.
/Bruce
