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[80.230.39.63]) by smtp.gmail.com with ESMTPSA id ffacd0b85a97d-42cb7f363c0sm39412154f8f.18.2025.11.25.23.15.18 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 25 Nov 2025 23:15:19 -0800 (PST) Date: Wed, 26 Nov 2025 02:15:16 -0500 From: "Michael S. Tsirkin" To: Simon Schippers Cc: Jason Wang , willemdebruijn.kernel@gmail.com, andrew+netdev@lunn.ch, davem@davemloft.net, edumazet@google.com, kuba@kernel.org, pabeni@redhat.com, eperezma@redhat.com, jon@nutanix.com, tim.gebauer@tu-dortmund.de, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux.dev Subject: Re: [PATCH net-next v6 0/8] tun/tap & vhost-net: netdev queue flow control to avoid ptr_ring tail drop Message-ID: <20251126021327-mutt-send-email-mst@kernel.org> References: <20251120152914.1127975-1-simon.schippers@tu-dortmund.de> Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Fri, Nov 21, 2025 at 10:22:54AM +0100, Simon Schippers wrote: > I agree, but I really would like to reduce the buffer bloat caused by the > default 500 TUN / 1000 TAP packet queue without losing performance. that default is part of the userspace API and can't be changed. just change whatever userspace is creating your device. -- MST