-----Original Message----- From: Eric Dumazet edumazet@google.com Sent: Thursday, August 21, 2025 2:24 PM To: Chia-Yu Chang (Nokia) chia-yu.chang@nokia-bell-labs.com Cc: pabeni@redhat.com; linux-doc@vger.kernel.org; corbet@lwn.net; horms@kernel.org; dsahern@kernel.org; kuniyu@amazon.com; bpf@vger.kernel.org; netdev@vger.kernel.org; dave.taht@gmail.com; jhs@mojatatu.com; kuba@kernel.org; stephen@networkplumber.org; xiyou.wangcong@gmail.com; jiri@resnulli.us; davem@davemloft.net; andrew+netdev@lunn.ch; donald.hunter@gmail.com; ast@fiberby.net; liuhangbin@gmail.com; shuah@kernel.org; linux-kselftest@vger.kernel.org; ij@kernel.org; ncardwell@google.com; Koen De Schepper (Nokia) koen.de_schepper@nokia-bell-labs.com; g.white@cablelabs.com; ingemar.s.johansson@ericsson.com; mirja.kuehlewind@ericsson.com; cheshire@apple.com; rs.ietf@gmx.at; Jason_Livingood@comcast.com; vidhi_goel@apple.com Subject: Re: [PATCH v15 net-next 08/14] tcp: accecn: AccECN needs to know delivered bytes
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On Fri, Aug 15, 2025 at 1:39 AM chia-yu.chang@nokia-bell-labs.com wrote:
From: Ilpo Järvinen ij@kernel.org
AccECN byte counter estimation requires delivered bytes which can be calculated while processing SACK blocks and cumulative ACK. The delivered bytes will be used to estimate the byte counters between AccECN option (on ACKs w/o the option).
Non-SACK calculation is quite annoying, inaccurate, and likely bogus.
Does it mean AccECN depends on SACK ?
In fact, AccECN does not depend on SACK to function; however, it would be more accurate if SACK were there. In order to avoid confusion, I will remove this old comment in the next version.
Chia-Yu