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charset=us-ascii Content-Disposition: inline In-Reply-To: X-Rspamd-Queue-Id: 5D43AC0012 X-Rspam-User: X-Stat-Signature: 84t9skmwz3ix693b47zywud69t5rdz6e X-Rspamd-Server: rspam09 X-HE-Tag: 1780674120-641972 X-HE-Meta: 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 b4UHrJjw grqsTIb/bGa+gTo+vW9S0owYDM/iG+vFJk2FEcBN9/WCVswh+4ZIuTwfqinLH2+X2A5gQvZUDfP5mDUWtMiz6GDb0P7oF4eUiZK4jJWB+zeAMebf+DF/3/8Ab2bQG4upctnrsy3TIrOAGOg68GrwgeQ2hPvwSWXfF3Q3PiMuMsuhKgLecS8cVlcDuSzqTzdtHmaR9GVLPLOYGxdmWzm98P9xagc/9WBTT21qnq6/yKR6DJTeFoK7WJhjc0KIFHd0STt6M6vFTwMO3FkHnfjRjVoq/Q1hTfVUzcnldcnT2eoKsQ/TEXe7eChU9lJRqLBOfzOMALsY38GqN8+cC9gzPsEtD7Xxp/LkurSaC755o4/LNV4s8xA3AX7Pz7Lr2w7C5fbsUlhYa7o2mhv0= Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Thu, Jun 04, 2026 at 06:15:41PM +0200, Willy Tarreau wrote: > On Thu, Jun 04, 2026 at 08:58:33AM -0700, Linus Torvalds wrote: > > On Thu, 4 Jun 2026 at 08:53, Willy Tarreau wrote: > > > > > > > It looks like you're actually doing exactly the thing that I thought > > > > was crazy and wouldn't even work reliably: you change the > > > > common_response[] contents dynamically *after* the vmsplice, and > > > > depend on the fact that changing it in user space changes the buffer > > > > in the pipe too. > > > > > > No no, it's definitely not doing that (or it's a bug, but it's not > > > supposed to happen). I'm perfectly aware that one must definitely not > > > do that, and it's a guarantee the user of vmsplice() must provide. > > > > Whew, good. > > > > In that case, can you just try the vmsplice patch series (Christian > > already found a bug, but I don't think it will necessarily matter in > > practice - famous last words) and that test patch of mine, and see if > > it all (a) works for you and (b) if you have any numbers for > > performance that would be *great*. > > Yes I wanted to do that and noted it on my todo list yesterday when > noticing the ongoing discussion. Just been super busy with yesterday's > by-yearly release ;-) But at least I wanted to share quick feedback in > this thread about existing uses. OK so I could run the test this afternoon, with: - ddd664bbff63 Merge tag 'net-7.1-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net (v7.1-rc6-178) - the same with Christian's vfs-7.2.vmsplice branch merged into it ( 8d86fcfc2857 include/linux/splice.h: trivial fix: declerations -> declarations) Both show 71-72 Gbps of TLS traffic per core on my test utility (I stopped at 3 cores since having only 2x100G at the moment), so for this use case I'm not impacted by the change. I noted that I will have to reconsider other options for the cache (send(MSG_ZEROCOPY) probably) but in my case since the code doesn't exist yet it's not per-se a userland breakage, but a change of plans. I just hope I'll find my way through the alternate solution. FWIW for Christian's branch: Tested-by: Willy Tarreau Willy