From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 2838E2C374B; Tue, 9 Sep 2025 09:24:45 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1757409886; cv=none; b=DhX4mAFzMZIYapxI4nqP1pa0ZMUEDk0AdrY0A2avypTyjLP/rZFDN6cWFjnbczK+knRp5OZ94+01yb6GZSaWrlCX6NiEjVYBxnRLtZiC7WtlVJG9VpsOy48NC/ZIHC9NN8EhncDapnc5n60EnJuYkAgY8KHua4kG/ALmGb9Q64Y= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1757409886; c=relaxed/simple; bh=crP1HHzUmFBEyI7U2LL0UP+sAsNP6hV3Iu/cO7wIU6k=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=cUeVhleac7EBI6DGKQdw1anjzCYnoPECunPZiwEksKtgzHBjKRUPLaK5qTRL4iKUHQrt88m34+J2hrn4P0tdeIUvSKOC8sFQw3i/ruWkaWVwV74Ll0/rqrrBCvwWpxjnR+m2vyIhkQXDtCc/2JAar1SsioQRh1OFSZtD0GnnzBg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=g6CQuOTf; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="g6CQuOTf" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 10D47C4CEF4; Tue, 9 Sep 2025 09:24:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1757409885; bh=crP1HHzUmFBEyI7U2LL0UP+sAsNP6hV3Iu/cO7wIU6k=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=g6CQuOTfKtoiQ/KZtU1Hkxb8kmHFq43k7C2LU67Tc9yTDEP2/rb4MD2cjYuRBQxrW bBrhW3nEpYsiCYgq2JAuk1zUDH50a3mOn2LSYSd6KWatvJuiLjQ7AcXgoaira4tkLN 0b5czq7VkMnnf+NCqde3FNb11pT3Bn5kv7zlbHiW7D/A7ZuMANH43M6Lv13zX48yIT tqfuCSj2wI8gAMLc48mbgAjD1Y+LzXL1UnxrS1r+U1ceN6U/PeQdCIwFpbN9ocp3OW 2Hjlcenw2uRke3iW50LYNy1o+zUr8Qr+RoFd8wAl+O3kScdsIXKPmX9V5S0tOh4eRB c4r8EeWfG0sSw== Date: Tue, 9 Sep 2025 10:24:41 +0100 From: Simon Horman To: Jakub Kicinski Cc: davem@davemloft.net, netdev@vger.kernel.org, edumazet@google.com, pabeni@redhat.com, andrew+netdev@lunn.ch, shuah@kernel.org, linux-kselftest@vger.kernel.org Subject: Re: [PATCH net-next] selftests: net: speed up pmtu.sh by avoiding unnecessary cleanup Message-ID: <20250909092441.GG2015@horms.kernel.org> References: <20250906214535.3204785-1-kuba@kernel.org> Precedence: bulk X-Mailing-List: linux-kselftest@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250906214535.3204785-1-kuba@kernel.org> On Sat, Sep 06, 2025 at 02:45:35PM -0700, Jakub Kicinski wrote: > The pmtu test takes nearly an hour when run on a debug kernel > (10min on a normal kernel, so the debug slow down is quite significant). > NIPA tries to ensure all results are delivered by a certain deadline > so this prevents it from retrying the test in case of a flake. > > Looks like one of the slowest operations in the test is calling out > to ./openvswitch/ovs-dpctl.py to remove potential leftover OvS interfaces. > Check whether the interfaces exist in the first place in sysfs, > since it can be done directly in bash it is very fast. > > This should save us around 20-30% of the test runtime. > > Signed-off-by: Jakub Kicinski It would be interesting to know why this is so slow. But I agree that avoiding unnecessary work is a good approach if it is slow. And that appears to be the case. Reviewed-by: Simon Horman