Re: [PATCH 11/11] selftests: net/fcnal: Reduce client timeout

[Leonard Crestez]

On 07.10.2021 04:17, David Ahern wrote:
> On 10/6/21 3:26 PM, Leonard Crestez wrote:
> > On 06.10.2021 18:01, David Ahern wrote:
> > > On 10/6/21 5:47 AM, Leonard Crestez wrote:
> > > > Reduce default client timeout from 5 seconds to 500 miliseconds.
> > > > Can be overridden from environment by exporting NETTEST_CLIENT_TIMEOUT=5
> > > >
> > > > Some tests need ICMP timeouts so pass an explicit -t5 for those.
> > > >
> > > > Signed-off-by: Leonard Crestez <cdleonard@xxxxxxxxx>
> > > > ---
> > > >    tools/testing/selftests/net/fcnal-test.sh | 17 +++++++++++------
> > > >    1 file changed, 11 insertions(+), 6 deletions(-)
> > >
> > > The problem with blindly reducing the timeouts is running the script on
> > > a loaded server. Some tests are expected to timeout while for tests a
> > > timeout is a failure.
> >
> > Keeping the default value "5" would be fine as long as it is possible to
> > override externally and get fast results on a mostly-idle machine.
>
> 5 is the default for nettest.c; the test script passes in -t1 for all tests.

An explicit -t is only passed for some of the tests

$ grep -c nettest.*-r tools/testing/selftests/net/fcnal-test.sh
243
$ grep -c nettest.*-t tools/testing/selftests/net/fcnal-test.sh
15

> > Placing a default value in the environment which is overriden by certain
> > tests achieves that.
> >
> > In theory it would also be possible for fcnal-test.sh to parse as
> > "--timeout" option and pass it into every single test but that solution
> > would cause much more code churn.
> >
> > Having default values in environment variables that can still be
> > overridden by command-line arguments is a common pattern in many tools.
> > It also avoids having to pass-through every flag through every
> > intermediate wrapper.
>
> I do not agree with env variables here.

Would you agree with adding an option to fcnal-test.sh which decreases 
timeouts passed to nettest client calls?