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Mon, 16 Mar 2026 18:18:16 -0700 (PDT) Message-ID: <54f95b7a-45de-4353-9308-12cd64dbe894@kernel.dk> Date: Mon, 16 Mar 2026 19:18:15 -0600 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [RFC PATCH 0/2] io_uring: add IPC channel infrastructure To: Daniel Hodges Cc: Daniel Hodges , io-uring@vger.kernel.org, linux-kernel@vger.kernel.org References: <20260313130739.23265-1-git@danielhodges.dev> <20260314135053.3334-1-git@danielhodges.dev> <873d56d8-6c1c-447f-ae70-870417c6de5a@kernel.dk> Content-Language: en-US From: Jens Axboe In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 3/16/26 5:13 PM, Daniel Hodges wrote: > On Mon, Mar 16, 2026 at 04:17:05PM -0600, Jens Axboe wrote: >> On 3/16/26 6:49 AM, Daniel Hodges wrote: >>> On Sat, Mar 14, 2026 at 10:54:15AM -0600, Jens Axboe wrote: >>>> On 3/14/26 7:50 AM, Daniel Hodges wrote: >>>>> On Thu, Mar 13, 2026 at 01:07:37PM +0000, Daniel Hodges wrote: >>>>>> Performance (virtme-ng VM, single-socket, msg_size sweep 64B-32KB): >>>>>> >>>>>> Point-to-point latency (64B-32KB messages): >>>>>> io_uring unicast: 597-3,185 ns/msg (within 1.5-2.5x of pipe for small msgs) >>>>> >>>>> Benchmark sources used to generate the numbers in the cover letter: >>>>> >>>>> io_uring IPC modes (broadcast, multicast, unicast): >>>>> https://gist.github.com/hodgesds/fbcd8bb8497bc0ec2bf1f95244a984fe#file-io_uring_ipc_bench-c >>>>> >>>>> IPC comparison (pipes, unix sockets, shm+eventfd): >>>>> https://gist.github.com/hodgesds/fbcd8bb8497bc0ec2bf1f95244a984fe#file-ipc_comparison_bench-c >>>> >>>> Thanks for sending these, was going to ask you about them. I'll take a >>>> look at your patches Monday. >>>> >>>> -- >>>> Jens Axboe >>> >>> No rush, thanks for taking the time! >> >> I took a look - and I think it's quite apparent that it's a AI vibe >> coded patch. Hence my first question is, do you have a specific use case >> in mind? Or phrased differently, was this done for a specific use case >> you have and want to pursue, or was it more of a "let's see if we can do >> this and what it'd look like" kind of thing? >> >> I have a lot of comments on the patch itself, but let's establish the >> motivation here first. >> >> -- >> Jens Axboe > > I've been helping Alexandre prototype a D-Bus broker replacement that > scales better on large machines. Here's some docs/benchmarks: > https://github.com/fiorix/sbus/blob/main/sbus-broker/docs/analysis.md > > The idea for this RFC by trying to come up with a design if D-Bus was to > be built from the ground so that it could scale on large machines. D-Bus > was built because the kernel never really had a broadcast/multicast > solution for IPC and kdbus demonstrated that moving dbus into the kernel > wasn't viable either. So that's where I sort of landed on the idea of > what if io_uring could be used for this type of IPC. > > There isn't a working io_uring backed D-Bus implementation yet as > it would require features that aren't in this patch such a handling > credentials etc. I fully acknowledge I had AI help in working on this, > but if this idea make sense I would appreciate some human direction. If > it seems like it could be feasible from your pespective I would like to > try to give it a proper attempt. Thanks! OK, thanks for the explanation! I do think it makes sense to do, and starting with the basic mechanism first makes sense. I haven't read your link yet, but I suppose that had details on what else would be needed feature wise on top of the base? -- Jens Axboe