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[204.195.123.141]) by smtp.gmail.com with ESMTPSA id l185-20020a6325c2000000b005dc19ac7162sm1652953pgl.3.2024.02.07.07.03.02 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 07 Feb 2024 07:03:03 -0800 (PST) Date: Wed, 7 Feb 2024 07:03:01 -0800 From: Stephen Hemminger To: Dave Taht via Bloat Cc: Dave Taht , Michael Welzl , Linux Kernel Network Developers Subject: Re: [Bloat] Trying to *really* understand Linux pacing Message-ID: <20240207070301.30c92e23@hermes.local> In-Reply-To: References: <1BAA689A-D44E-4122-9AD8-25F6D024377E@ifi.uio.no> 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 Wed, 7 Feb 2024 07:05:27 -0500 Dave Taht via Bloat wrote: > I also tend to think that attempting it in various cloudy > environments and virtualization schemes, and with certain drivers, the > side effects are not as well understood as I would like. For example, > AWS's nitro lacks BQL as does virtio-net. FYI - Microsoft Azure drivers don't do BQL either. Both netvsc and mana. The problem is that implementing BQL is not as easy as it looks and has possibility of introducing bugs. One big customer with a stuck connection totally negates any benefit! For virtio, there have been several attempts at BQL and they never worked perfectly.