From owner-freebsd-net@freebsd.org Wed Aug 17 17:25:57 2016 Return-Path: Delivered-To: freebsd-net@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 2F631BBDF52 for ; Wed, 17 Aug 2016 17:25:57 +0000 (UTC) (envelope-from adrian.chadd@gmail.com) Received: from mail-io0-x244.google.com (mail-io0-x244.google.com [IPv6:2607:f8b0:4001:c06::244]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority G2" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id E64A114ED for ; Wed, 17 Aug 2016 17:25:56 +0000 (UTC) (envelope-from adrian.chadd@gmail.com) Received: by mail-io0-x244.google.com with SMTP id q83so11171786iod.2 for ; Wed, 17 Aug 2016 10:25:56 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:sender:in-reply-to:references:from:date:message-id :subject:to:cc; bh=gsjZkWbm388YQrvT8Lebs2P2+FRbgO3LLQMQ57MiebY=; b=HKTw0/QK/OUMQQQN2nqJ2x1umhb1T54SmnEEfrTGljrtaAgiqkLO2hHEPIP9SL4gGH jVA3VNhSoWmYFZUD5ZLWJl5y5SVKLVmonnmXbktAdAA5h+V/91xp71k1E56MOCjGDVK5 0xytVLIGDYf3VSCse+LPEQAbwtWNV7OVZCT8TP797aDTD+DDnF3z4MadfZWcKeZPY3yh n9OrH4cQalppAeiCl3VwxwQGirBGJwdceEXf2mIc28snwMujKtBiEvJ93MTaZFZ9wQtq JCaAoIqmBv9rx3IIQpCFTeCARTF4piBY/K1GQTSl0lrQk4tXcxhoc6EYF60mrBXsViN6 K5uA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:mime-version:sender:in-reply-to:references:from :date:message-id:subject:to:cc; bh=gsjZkWbm388YQrvT8Lebs2P2+FRbgO3LLQMQ57MiebY=; b=We5coUJ64c3IVfNBwFeE+LBGpA5wY0igGLWvvXugqq11l1EA6BdIbr7bEr89JMrvPa TWdivbv8/t2p2KbioQI1m0n7bqJtMPen9CQOJNg/bJmalvv5b1rsY0D+CrKZBIfpEsgl x9UkXHx/jhKhe48QW5p0c9G3p6e1V6vmGhLIB1J96vCsqktweMS1tlC84s9t2KtbQvha KhMFU1fdIkIvIcEkzJqMjwxlCBecekW5I6IRuSNR0tlRFlNB/4my5GyLgbVIVcvL8LXB VMzzSpHUBI9Dd+6OnTFk2jg3n8fqakB73kE+uCqZYH0kr/G2evjiH9opMtiwJB1T6KoT rwKQ== X-Gm-Message-State: AEkoouuyrHLNg9BtjtqtqwrEtUce+lQDCUbH3+yu+YjdDxlleePTIs8XcCThsRzfGyTO1AEu9poJVACkKDNsWg== X-Received: by 10.107.144.10 with SMTP id s10mr46300654iod.165.1471454756413; Wed, 17 Aug 2016 10:25:56 -0700 (PDT) MIME-Version: 1.0 Sender: adrian.chadd@gmail.com Received: by 10.36.141.129 with HTTP; Wed, 17 Aug 2016 10:25:55 -0700 (PDT) In-Reply-To: <9ED07C8F-4E43-4C5F-A893-61F9ADA76E56@gmail.com> References: <3C0D892F-2BE8-4650-B9FC-93C8EE0443E1@gmail.com> <3B164B7B-CBFB-4518-B57D-A96EABB71647@gmail.com> <5D6DF8EA-D9AA-4617-8561-2D7E22A738C3@gmail.com> <7DD30CE7-32E6-4D26-91D4-C1D4F2319655@gmail.com> <91AEB1BD-44EA-43AD-A9A1-6DEBF367DF9B@gmail.com> <9ED07C8F-4E43-4C5F-A893-61F9ADA76E56@gmail.com> From: Adrian Chadd Date: Wed, 17 Aug 2016 10:25:55 -0700 X-Google-Sender-Auth: O3NHHtPMrUgQxNMbbnHnHSleK-E Message-ID: Subject: Re: Unstable local network throughput To: Ben RUBSON Cc: FreeBSD Net Content-Type: text/plain; charset=UTF-8 X-BeenThere: freebsd-net@freebsd.org X-Mailman-Version: 2.1.22 Precedence: list List-Id: Networking and TCP/IP with FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 17 Aug 2016 17:25:57 -0000 On 17 August 2016 at 08:43, Ben RUBSON wrote: > >> On 17 Aug 2016, at 17:38, Adrian Chadd wrote: >> >> [snip] >> >> ok, so this is what I was seeing when I was working on this stuff last. >> >> The big abusers are: >> >> * so_snd lock, for TX'ing producer/consumer socket data >> * tcp stack pcb locking (which rss tries to work around, but it again >> doesn't help producer/consumer locking, only multiple sockets) >> * for some of the workloads, the scheduler spinlocks are pretty >> heavily contended and that's likely worth digging into. >> >> Thanks! I'll go try this on a couple of boxes I have with >> intel/chelsio 40g hardware in it and see if I can reproduce it. (My >> test boxes have the 40g NICs in NUMA domain 1...) > > You're welcome, happy to help and troubleshoot :) > > What about the performance which differs from one reboot to another, > as if the NUMA domains have switched ? (0 to 1 & 1 to 0) > Did you already see this ? I've seen some varying behaviours, yeah. There are a lot of missing pieces in kernel-side NUMA, so a lot of the kernel memory allocation behaviours are undefined. Well, tehy'e defined; it's just there's no way right now for the kernel (eg mbufs, etc) to allocate domain local memory. So it's "by accident", and sometimes it's fine; sometimes it's not. -adrian