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Date: Thu, 7 Sep 2023 11:10:50 -0700
From: Jakub Kicinski <kuba@kernel.org>
To: Eric Dumazet <edumazet@google.com>
Cc: "David S . Miller" <davem@davemloft.net>, Paolo Abeni
 <pabeni@redhat.com>, netdev@vger.kernel.org, eric.dumazet@gmail.com, Soheil
 Hassas Yeganeh <soheil@google.com>, Neal Cardwell <ncardwell@google.com>,
 Yuchung Cheng <ycheng@google.com>
Subject: Re: [RFC net-next 4/4] tcp: defer regular ACK while processing
 socket backlog
Message-ID: <20230907111050.30425753@kernel.org>
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On Thu, 7 Sep 2023 20:05:29 +0200 Eric Dumazet wrote:
> > Interesting. Some folks at Meta were recently looking into parsing RPCs
> > in the kernel to avoid unnecessary wakeups. Poor man's KCM using BPF
> > sockmaps. Passing message size hints from the sender would solve so
> > many problems..  
> 
> Yes, RPC headers make things easier for sure.
> 
> (we internally have something similar named autolowat, where we parse
> headers to set sk->sk_rcvlowat dynamically)

Could this be turned into a BPF hook, possibly?
That's basically what I suggested the BPF people did but they like 
to rewrite everything.