From owner-freebsd-current@freebsd.org Fri Sep 15 15:20:07 2017 Return-Path: Delivered-To: freebsd-current@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 C0F7BE1CD00 for ; Fri, 15 Sep 2017 15:20:07 +0000 (UTC) (envelope-from wlosh@bsdimp.com) Received: from mail-io0-x241.google.com (mail-io0-x241.google.com [IPv6:2607:f8b0:4001:c06::241]) (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 8D7AD6BCA8 for ; Fri, 15 Sep 2017 15:20:07 +0000 (UTC) (envelope-from wlosh@bsdimp.com) Received: by mail-io0-x241.google.com with SMTP id d16so4228290ioj.2 for ; Fri, 15 Sep 2017 08:20:07 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bsdimp-com.20150623.gappssmtp.com; s=20150623; h=mime-version:sender:in-reply-to:references:from:date:message-id :subject:to:cc; bh=EzaKi4W7bV9F+5V+tpxPcwHYnQMzrB2TpV0qEi/kXnA=; b=gQIzAk/Rqp6BUyZIj4ZOEQdPc1PbcTV9aI7bxZjYHsoawp5WlOTJGTk5k2LnVioiJ2 AuzR8ALMCg7UTuuzYu9Dtb4izwMOKAVq/3ee1J88jVqn7pdv3+3QqXczZNvUrfrB3mFE y/3jDdNTkTXX1MxuIt5FsyIXiQnU37F2d4BjUF9MkhZytsiF83JmELtLIxpDKNgXTeJK XO6K7OQr8VGUhuUg1Lux1wumJbrtuN1bQBZuMDxXGXNy7FeMOFaAohBBrenWYeGvDsIj vzX46VpwP0I9JEPvQGqZ2EabHR9i+4bpYux4OW/n7dVUPfVJFr4z/uZU6QKA8vkAGd9/ x37Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:sender:in-reply-to:references:from :date:message-id:subject:to:cc; bh=EzaKi4W7bV9F+5V+tpxPcwHYnQMzrB2TpV0qEi/kXnA=; b=m5tftrHm0kC4vq328IiGw04q0aAtUVbgbqjzOnphTFi6PSVEzd2kl3OtOaPE1+YvFz AUiPAH9h9kYOXFDLO4iMJTr0tRuUgQp6kHZoCj90KtlnNF22BCXkrxSvW5zt05QnCwmI Fn65MQGkxbvbLIBGSMZfSJalpDSwLyNKn1Zk1YjNHayEYknM4P5YEgoIFsi/kJXViFbU ihkSDYlP74cet+kfdm7/EATPN7fuAHR8j9Q1qDkx0P6sSq7iXFM/hx56gK2pL96gjTta A81EzVhIfgigb0MAJ3DJu0pq+PEo5Y7s8bnDhBZ28CEkESO+tvRbQ8PnynvwTO1aI2+C rdAw== X-Gm-Message-State: AHPjjUiGiG9sLaiyXB4KugZKsvCip2fpR60BnhXEs0W5ho3FsjwZAhF9 VeZXFd2hS7WuJ5EeVLE4b+1E7z9S1bk8v1Hawz0hOg== X-Google-Smtp-Source: AOwi7QAULABQd7EypuBFdlw4QaN6PQOJtHdkDZwI8wxv/Ko1WOG4q8eRVqltVhnXNMiH8Q2MMMkOMIzfcv9tlb1Eh/A= X-Received: by 10.107.7.161 with SMTP id g33mr7814804ioi.169.1505488806773; Fri, 15 Sep 2017 08:20:06 -0700 (PDT) MIME-Version: 1.0 Sender: wlosh@bsdimp.com Received: by 10.79.10.71 with HTTP; Fri, 15 Sep 2017 08:20:05 -0700 (PDT) X-Originating-IP: [50.253.99.174] In-Reply-To: References: <0100015c6fc1167c-6e139920-60d9-4ce3-9f59-15520276aebb-000000@email.amazonses.com> <972dbd34-b5b3-c363-721e-c6e48806e2cd@elischer.org> <3719c729-9434-3121-cf52-393a4453d0b2@freebsd.org> From: Warner Losh Date: Fri, 15 Sep 2017 09:20:05 -0600 X-Google-Sender-Auth: mAEe_RQ8hj_1gtg5Cja07JjmdEM Message-ID: Subject: Re: Time to increase MAXPHYS? To: Nikolai Lifanov Cc: Allan Jude , FreeBSD Current Content-Type: text/plain; charset="UTF-8" X-Content-Filtered-By: Mailman/MimeDel 2.1.23 X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 15 Sep 2017 15:20:07 -0000 On Fri, Sep 15, 2017 at 9:18 AM, Nikolai Lifanov wrote: > On 6/3/17 11:55 PM, Allan Jude wrote: > > On 2017-06-03 22:35, Julian Elischer wrote: > >> On 4/6/17 4:59 am, Colin Percival wrote: > >>> On January 24, 1998, in what was later renumbered to SVN r32724, dyson@ > >>> wrote: > >>>> Add better support for larger I/O clusters, including larger physical > >>>> I/O. The support is not mature yet, and some of the underlying > >>>> implementation > >>>> needs help. However, support does exist for IDE devices now. > >>> and increased MAXPHYS from 64 kB to 128 kB. Is it time to increase it > >>> again, > >>> or do we need to wait at least two decades between changes? > >>> > >>> This is hurting performance on some systems; in particular, EC2 "io1" > >>> disks > >>> are optimized for 256 kB I/Os, EC2 "st1" (throughput optimized > >>> spinning rust) > >>> disks are optimized for 1 MB I/Os, and Amazon's NFS service (EFS) > >>> recommends > >>> using a maximum I/O size of 1 MB (and despite NFS not being *physical* > >>> I/O it > >>> seems to still be limited by MAXPHYS). > >>> > >> We increase it in freebsd 8 and 10.3 on our systems, Only good results. > >> > >> sys/sys/param.h:#define MAXPHYS (1024 * 1024) /* max raw I/O > >> transfer size */ > >> > >> _______________________________________________ > >> freebsd-current@freebsd.org mailing list > >> https://lists.freebsd.org/mailman/listinfo/freebsd-current > >> To unsubscribe, send any mail to "freebsd-current-unsubscribe@ > freebsd.org" > > > > At some point Warner and I discussed how hard it might be to make this a > > boot time tunable, so that big amd64 machines can have a larger value > > without causing problems for smaller machines. > > > > ZFS supports a block size of 1mb, and doing I/Os in 128kb negates some > > of the benefit. > > > > I am preparing some benchmarks and other data along with a patch to > > increase the maximum size of pipe I/O's as well, because using 1MB > > offers a relatively large performance gain there as well. > > > > Hi! > > I also migrated to 1mb recordsize. What's the status of your patches > and/or making MAXPHYS a boot-time tunable? I can help test these. > Still in my queue to do. Warner