On Sat, Aug 15, 2026, at 02:07, Matthieu Baerts wrote: > Hi Alice, > > On 14/08/2026 21:41, Alice Mikityanska wrote: >> From: Alice Mikityanska <[email protected]> >> >> CONFIG_DEBUG_NET kernels run slower and generate fewer BIG TCP packets, >> making the test flaky on upstream CI runners. Lower the default >> threshold for those kernels. > > Thank you for looking at that! > >> Signed-off-by: Alice Mikityanska <[email protected]> >> --- >> tools/testing/selftests/net/big_tcp_tunnels.sh | 18 ++++++++++++++++-- >> 1 file changed, 16 insertions(+), 2 deletions(-) >> >> diff --git a/tools/testing/selftests/net/big_tcp_tunnels.sh >> b/tools/testing/selftests/net/big_tcp_tunnels.sh >> index 9b7d0456bcc1..e27774eae20e 100755 >> --- a/tools/testing/selftests/net/big_tcp_tunnels.sh >> +++ b/tools/testing/selftests/net/big_tcp_tunnels.sh >> @@ -17,11 +17,25 @@ CLIENT_IP6="2001:db8::1:2" >> CLIENT_IP4_TUN="192.168.2.2" >> CLIENT_IP6_TUN="2001:db8::2:2" >> >> -: "${PACKETS_THRESHOLD:=1000}" >> - >> # Kselftest framework requirement - SKIP code is 4. >> ksft_skip=4 >> >> +is_debug() { >> + local config="/proc/config.gz" >> + [ -f "$config" ] || config="/boot/config-$(uname -r)" >> + [ -f "$config" ] || return 1 # No config found; assume non-debug. >> + gzip -dcfq "$config" | grep -qx 'CONFIG_DEBUG_NET=y' || return 1 > > Are you sure it is CONFIG_DEBUG_NET that causes that? It shouldn't be > that heavy. > > Do you not want to change the thresholds only for the -dbg runners using > kernel/configs/debug.config? If yes, you should check if > KSFT_MACHINE_SLOW == yes:
Thanks for the suggestion! I'll switch to KSFT_MACHINE_SLOW. > https://github.com/linux-netdev/nipa/wiki/How-to-run-netdev-selftests-CI-style#dealing-with-slow-runners-in-performancelatency-tests > > Cheers, > Matt > -- > Sponsored by the NGI0 Core fund.
