From 555e5531635a7c5dba663d06cea240362624dfde Mon Sep 17 00:00:00 2001 From: Jakub Kicinski Date: Sat, 17 Aug 2024 13:36:59 -0700 Subject: [PATCH] selftests: net/forwarding: spawn sh inside vrf to speed up ping loop Looking at timestamped output of netdev CI reveals that most of the time in forwarding tests for custom route hashing is spent on a single case, namely the test which uses ping (mausezahn does not support flow labels). On a non-debug kernel we spend 714 of 730 total test runtime (97%) on this test case. While having flow label support in a traffic gen tool / mausezahn would be best, we can significantly speed up the loop by putting ip vrf exec outside of the iteration. In a test of 1000 pings using a normal loop takes 50 seconds to finish. While using: ip vrf exec $vrf sh -c "$loop-body" takes 12 seconds (1/4 of the time). Some of the slowness is likely due to our inefficient virtualization setup, but even on my laptop running "ip link help" 16k times takes 25-30 seconds, so I think it's worth optimizing even for fastest setups. Reviewed-by: Ido Schimmel Tested-by: Ido Schimmel Reviewed-by: Hangbin Liu Link: https://patch.msgid.link/20240817203659.712085-1-kuba@kernel.org Signed-off-by: Jakub Kicinski --- .../selftests/net/forwarding/custom_multipath_hash.sh | 8 ++++---- .../selftests/net/forwarding/gre_custom_multipath_hash.sh | 8 ++++---- .../net/forwarding/ip6gre_custom_multipath_hash.sh | 8 ++++---- 3 files changed, 12 insertions(+), 12 deletions(-) diff --git a/tools/testing/selftests/net/forwarding/custom_multipath_hash.sh b/tools/testing/selftests/net/forwarding/custom_multipath_hash.sh index 1783c10215e5c..7d531f7091e6f 100755 --- a/tools/testing/selftests/net/forwarding/custom_multipath_hash.sh +++ b/tools/testing/selftests/net/forwarding/custom_multipath_hash.sh @@ -224,10 +224,10 @@ send_dst_ipv6() send_flowlabel() { # Generate 16384 echo requests, each with a random flow label. - for _ in $(seq 1 16384); do - ip vrf exec v$h1 \ - $PING6 2001:db8:4::2 -F 0 -c 1 -q >/dev/null 2>&1 - done + ip vrf exec v$h1 sh -c \ + "for _ in {1..16384}; do \ + $PING6 2001:db8:4::2 -F 0 -c 1 -q >/dev/null 2>&1; \ + done" } send_src_udp6() diff --git a/tools/testing/selftests/net/forwarding/gre_custom_multipath_hash.sh b/tools/testing/selftests/net/forwarding/gre_custom_multipath_hash.sh index 9788bd0f6e8b3..dda11a4a9450a 100755 --- a/tools/testing/selftests/net/forwarding/gre_custom_multipath_hash.sh +++ b/tools/testing/selftests/net/forwarding/gre_custom_multipath_hash.sh @@ -319,10 +319,10 @@ send_dst_ipv6() send_flowlabel() { # Generate 16384 echo requests, each with a random flow label. - for _ in $(seq 1 16384); do - ip vrf exec v$h1 \ - $PING6 2001:db8:2::2 -F 0 -c 1 -q >/dev/null 2>&1 - done + ip vrf exec v$h1 sh -c \ + "for _ in {1..16384}; do \ + $PING6 2001:db8:2::2 -F 0 -c 1 -q >/dev/null 2>&1; \ + done" } send_src_udp6() diff --git a/tools/testing/selftests/net/forwarding/ip6gre_custom_multipath_hash.sh b/tools/testing/selftests/net/forwarding/ip6gre_custom_multipath_hash.sh index 2ab9eaaa5532a..e28b4a079e525 100755 --- a/tools/testing/selftests/net/forwarding/ip6gre_custom_multipath_hash.sh +++ b/tools/testing/selftests/net/forwarding/ip6gre_custom_multipath_hash.sh @@ -321,10 +321,10 @@ send_dst_ipv6() send_flowlabel() { # Generate 16384 echo requests, each with a random flow label. - for _ in $(seq 1 16384); do - ip vrf exec v$h1 \ - $PING6 2001:db8:2::2 -F 0 -c 1 -q >/dev/null 2>&1 - done + ip vrf exec v$h1 sh -c \ + "for _ in {1..16384}; do \ + $PING6 2001:db8:2::2 -F 0 -c 1 -q >/dev/null 2>&1; \ + done" } send_src_udp6()