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 3BA94630 for ; Wed, 18 Oct 2023 00:40:22 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="fLGJs1jl" Received: by smtp.kernel.org (Postfix) with ESMTPS id A18B5C433C9; Wed, 18 Oct 2023 00:40:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1697589622; bh=oSQbRF4OP4QhhdUhVVIYIq7V/k8xhzaHn6bU0DsDZnY=; h=Subject:From:Date:References:In-Reply-To:To:Cc:From; b=fLGJs1jl4LRgfIV4pJ6LCmRSJWrKul1B7VItLK6s0rWMPTrQqebf4VzfU+zZWBkoT 7IW+cdOSvs47HP/T8mI8kCLfQDD6KV2pR2RSfy4pF9fG07vOglsS+SO3RFqGTmE5vg CLCKv6NglE80WyUtTyNZnQ/Qe1m9I7ZPuafDcdhXKOOYaDf4SXzJJ4qowaeENGgXKY /0HzP+pAMtjPmDXQJ1OgxGlW3tqeqlowlWF99OeZ/jHLcoaGmrX0Oi0X8u4b8auvOq dYZLbTPJDsdTDFLmFzKEiXND0qEHo/XpmuBTwzaM28MlfTtF36gHTZ+wZs4jJTXHNQ GapvZmQPpHbiA== Received: from aws-us-west-2-korg-oddjob-1.ci.codeaurora.org (localhost.localdomain [127.0.0.1]) by aws-us-west-2-korg-oddjob-1.ci.codeaurora.org (Postfix) with ESMTP id 87233C04E24; Wed, 18 Oct 2023 00:40:22 +0000 (UTC) Content-Type: text/plain; charset="utf-8" Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Subject: Re: [PATCH net] tcp: fix excessive TLP and RACK timeouts from HZ rounding From: patchwork-bot+netdevbpf@kernel.org Message-Id: <169758962254.9987.492571478078988197.git-patchwork-notify@kernel.org> Date: Wed, 18 Oct 2023 00:40:22 +0000 References: <20231015174700.2206872-1-ncardwell.sw@gmail.com> In-Reply-To: <20231015174700.2206872-1-ncardwell.sw@gmail.com> To: Neal Cardwell Cc: davem@davemloft.net, kuba@kernel.org, edumazet@google.com, netdev@vger.kernel.org, ncardwell@google.com, ycheng@google.com Hello: This patch was applied to netdev/net.git (main) by Jakub Kicinski : On Sun, 15 Oct 2023 13:47:00 -0400 you wrote: > From: Neal Cardwell > > We discovered from packet traces of slow loss recovery on kernels with > the default HZ=250 setting (and min_rtt < 1ms) that after reordering, > when receiving a SACKed sequence range, the RACK reordering timer was > firing after about 16ms rather than the desired value of roughly > min_rtt/4 + 2ms. The problem is largely due to the RACK reorder timer > calculation adding in TCP_TIMEOUT_MIN, which is 2 jiffies. On kernels > with HZ=250, this is 2*4ms = 8ms. The TLP timer calculation has the > exact same issue. > > [...] Here is the summary with links: - [net] tcp: fix excessive TLP and RACK timeouts from HZ rounding https://git.kernel.org/netdev/net/c/1c2709cfff1d You are awesome, thank you! -- Deet-doot-dot, I am a bot. https://korg.docs.kernel.org/patchwork/pwbot.html