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From: Toke =?utf-8?Q?H=C3=B8iland-J=C3=B8rgensen?= <toke@toke.dk>
To: ooonea <ooonea@gmail.com>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>, Jiri Pirko <jiri@resnulli.us>,
 "David S . Miller" <davem@davemloft.net>, Eric Dumazet
 <edumazet@google.com>, Jakub Kicinski <kuba@kernel.org>, Paolo Abeni
 <pabeni@redhat.com>, Simon Horman <horms@kernel.org>,
 cake@lists.bufferbloat.net, netdev@vger.kernel.org,
 linux-kernel@vger.kernel.org
Subject: Re: [PATCH net] net/sched: sch_cake: fix autorate reconfiguration
 throttling
In-Reply-To: <20260816012109.2865223-1-ooonea@gmail.com>
References: <20260816012109.2865223-1-ooonea@gmail.com>
Date: Wed, 19 Aug 2026 12:08:52 +0200
X-Clacks-Overhead: GNU Terry Pratchett
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ooonea <ooonea@gmail.com> writes:

> CAKE's autorate-ingress path intends to limit shaper reconfiguration to
> once per 250 ms, but last_reconfig_time is only checked and never updated.
> Since the field stays zero, every qualifying capacity-estimate window can
> call cake_reconfigure(), causing avoidable rate churn and scheduler work
> under bursty traffic.
>
> Store the current timestamp when autorate actually reconfigures the qdisc
> so the guard enforces the intended interval.
>
> Fixes: 7298de9cd725 ("sch_cake: Add ingress mode")
> Assisted-by: Codex:gpt-5.5
> Signed-off-by: ooonea <ooonea@gmail.com>

Acked-by: Toke H=C3=B8iland-J=C3=B8rgensen <toke@toke.dk>