From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: passt.top; dmarc=none (p=none dis=none) header.from=gibson.dropbear.id.au Authentication-Results: passt.top; dkim=pass (2048-bit key; secure) header.d=gibson.dropbear.id.au header.i=@gibson.dropbear.id.au header.a=rsa-sha256 header.s=202512 header.b=SziYyPmZ; dkim-atps=neutral Received: from mail.ozlabs.org (gandalf.ozlabs.org [150.107.74.76]) by passt.top (Postfix) with ESMTPS id 268AF5A0271 for ; Mon, 08 Dec 2025 07:46:50 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gibson.dropbear.id.au; s=202512; t=1765176407; bh=WSu8r0pEOJKKv3kNp4OzFj4G/LOphWMTf/IEAtLtQxs=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=SziYyPmZJnu7I7ZBcQtEVqAk53r3ANJcTYPrtHvpkBw9u1Yra3dIJeEcTIjQi6dmC 5AiQVCPg7FxfVTrrf7vlWfNdwgPRasI6v3mQ1mRnHnyfT/ED1BUrq7AAIdJSL0vNb4 cgvfzp5f8qpUfwd921FUoL6Fdit9BJw+B72HhwE6JVs4i6UigyCKVUUwktzWI5lBqH 12lAVQB0RP6O7EhBUaXyiL+2CAa+TLxgBZIX9VP+pKdnfIzWnN5NqH6WYqOxpfI+iL 0vL5YCCI0hBwwO8ulC10Zkyg4T6HtDaq18L2iK6OS5U6JE042wrn7koU2oNgtj/W2t YGDtzoFQuh9Vg== Received: by gandalf.ozlabs.org (Postfix, from userid 1007) id 4dPsw763gXz4wCx; Mon, 08 Dec 2025 17:46:47 +1100 (AEDT) Date: Mon, 8 Dec 2025 17:46:43 +1100 From: David Gibson To: Stefano Brivio Subject: Re: [PATCH v2 0/9] tcp: Fix throughput issues with non-local peers Message-ID: References: <20251208002229.391162-1-sbrivio@redhat.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="93UxcrgC/f0XAtKw" Content-Disposition: inline In-Reply-To: <20251208002229.391162-1-sbrivio@redhat.com> Message-ID-Hash: NSSXCZGMVZEWDKXWL3X3UZMQ6C56VB3W X-Message-ID-Hash: NSSXCZGMVZEWDKXWL3X3UZMQ6C56VB3W X-MailFrom: dgibson@gandalf.ozlabs.org X-Mailman-Rule-Misses: dmarc-mitigation; no-senders; approved; emergency; loop; banned-address; member-moderation; nonmember-moderation; administrivia; implicit-dest; max-recipients; max-size; news-moderation; no-subject; digests; suspicious-header CC: passt-dev@passt.top, Max Chernoff X-Mailman-Version: 3.3.8 Precedence: list List-Id: Development discussion and patches for passt Archived-At: Archived-At: List-Archive: List-Archive: List-Help: List-Owner: List-Post: List-Subscribe: List-Unsubscribe: --93UxcrgC/f0XAtKw Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Mon, Dec 08, 2025 at 01:22:08AM +0100, Stefano Brivio wrote: > Patch 2/9 is the most relevant fix here, as we currently advertise a > window that might be too big for what we can write to the socket, > causing retransmissions right away and occasional high latency on > short transfers to non-local peers. >=20 > Mostly as a consequence of fixing that, we now need several > improvements and small fixes, including, most notably, an adaptive > approach to pick the interval between checks for socket-side ACKs > (patch 3/9), and several tricks to reliably trigger TCP buffer size > auto-tuning as implemented by the Linux kernel (patches 5/9 and 7/9). >=20 > These changes make some existing issues more relevant, fixed by the > other patches. I've made a number of comments through the series. I think they do want some consideration. But given this works to address a real problem empirically, I'm fine for this to be merged as is, with more polishing later. --=20 David Gibson (he or they) | I'll have my music baroque, and my code david AT gibson.dropbear.id.au | minimalist, thank you, not the other way | around. http://www.ozlabs.org/~dgibson --93UxcrgC/f0XAtKw Content-Type: application/pgp-signature; name=signature.asc -----BEGIN PGP SIGNATURE----- iQIzBAEBCgAdFiEEO+dNsU4E3yXUXRK2zQJF27ox2GcFAmk2dFIACgkQzQJF27ox 2Ge3lw/+Jeac8VNSd1IKY9XQMsBYnZ4leSFOR6xWHuLOptXsyoyye8B6G5xBPfdM RxNlGKDOqdtthXH6C18FVEvVBxdzy6Fi4EheBOwN31Iqcl4JIvoZwIIG3Bk08RIo dLRueBMTUunCKB0W+j/wmUyuqRjj24mZ9Ggs6kZRzegrCUEsEs2jVri/R6Xxf9CM Gem0ZoQImj3zBGRW5PutgykJeNJMpesOxejO62yV+HjXjIgl+OL81O/E5pLlTUJg b/BoRKly61ZF0pCMEcxjzNxmhBBm+xMdHOWJGukd5A02ztAKgBJdAwCdju/ihnjN oku75/bNM6heqF362lDJR/9kQEO0xsEbD2oaNrseFpbywFyQ+XqjxLJ5QozMNMwU IPXpyY4y/adj9XUL9X3+BYO4X0wzo5zrLfVESQrunkyscoZpO3MrP9VoPmGoTrrm ARlftCSPRz1V9s6MXuhcfUOv4KcyT4q1MLgYt1b5CEaMzHtmKIY5cENy881gyEx3 H0F0Ytj70qdrXA2eFkD7zddxToBA+ai0IoF8g3XA8cpvBVFULUGXyFZPbgYKtbEW eT6gozIMGPHS9kczc/xZdTJAAtD7vZ42lRZhB4c9K9p0aOTz5Blp0isIKaCCdnGW UEeU2maDkOEYvA07SNeMcXYT9X7RrOWFIbSDCrw6b+kXExRM+9s= =7ccJ -----END PGP SIGNATURE----- --93UxcrgC/f0XAtKw--