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[204.195.112.43]) by smtp.gmail.com with ESMTPSA id 98e67ed59e1d1-3a78e5fbf30sm7412249a91.16.2026.10.04.10.45.28 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 04 Oct 2026 10:45:28 -0700 (PDT) Date: Sun, 4 Oct 2026 10:45:26 -0700 From: Stephen Hemminger To: Christophe Burdinat Cc: "netdev@vger.kernel.org" Subject: Re: [BUG] net/sched: netem: delay correlation has no effect Message-ID: <20261004104526.56a61ca5@phoenix.local> In-Reply-To: References: Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit On Fri, 2 Oct 2026 16:50:07 +0000 Christophe Burdinat wrote: > Hello, > > Context: we found the following while evaluating a QUIC-based protocol (Media over QUIC) with netem-based network profiles from a 3GPP study (TR 26.934), where the reordering caused by per-packet jitter makes QUIC declare many packets lost and changes the results substantially. The following report has been generated with Claude code, but humanly reviewed. Thanks for the bug report. Will look into it but do not expect anything soon. This code is over 20 years old, and it may just be you are trying to use it in a way that was never intended.