From owner-svn-src-head@freebsd.org Thu Apr 14 22:02:14 2016 Return-Path: Delivered-To: svn-src-head@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 6ACABAECD4F; Thu, 14 Apr 2016 22:02:14 +0000 (UTC) (envelope-from yaneurabeya@gmail.com) Received: from mail-pa0-x22b.google.com (mail-pa0-x22b.google.com [IPv6:2607:f8b0:400e:c03::22b]) (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 3D87B11B1; Thu, 14 Apr 2016 22:02:14 +0000 (UTC) (envelope-from yaneurabeya@gmail.com) Received: by mail-pa0-x22b.google.com with SMTP id er2so20058395pad.3; Thu, 14 Apr 2016 15:02:14 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:subject:from:in-reply-to:date:cc :content-transfer-encoding:message-id:references:to; bh=hzrPXyyRfbfzi3coR7SP6cdX/FIJF0SqWiw5RvURoPI=; b=XVfvGL5jAFQyNN73irKtpcKu6qDwq+c9EwFTUT118vkH2IS6kOBHtzlFg2srqjJ5TZ AvIF0gcDExgipvH4N7BXauH+p53jMVDgwTuUHQXRm1N4g9r+yy1M82nZZLQApOkaTYZ2 UpKJOfnI1SeqkxZcvGPwcx9T1UGvaUsFu7wM/f8NJ9DQ7DirZhR0lynhRVLM+8HlaLcc 4SfYUppm9NCpPKOzyclHgTIMdUfJ9q5PJ6i9qkYDQ//Z66DWKbotZ+dhxICAgd9wGsl7 Q1owHQ9/EyVO8JhFOKm0oKcc/LP3m8cvRDama7EtAoZ/lCOHBPj+X1Tty5gHSOjqvitp SSMw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:mime-version:subject:from:in-reply-to:date:cc :content-transfer-encoding:message-id:references:to; bh=hzrPXyyRfbfzi3coR7SP6cdX/FIJF0SqWiw5RvURoPI=; b=PiHcpJwJzz7uAcNhRlKxsT2Tg0GTv4FKRxondaC8Nkqmg4F8ye1BpzBHh50WcQArXM w7vCBRnNqBQFCEiTBoErZjGNweeob7fyvWKKUW96uDTNR+GeigGjMtyUG7xb7p6Ddjmf YKM4q1i749khjU4HBN7Bn/o4oxes4pvrM/Oaue+s7zRCHFePRCy4MF6Zu8yUAWKEni2J L69g7Grq5hRPVJHqAL0Am57TrCPcmbIDKwQ0+pYA6MA25wsWEk+9SyiuJNvmnuomdefE nNIhz5PEK7vbNNqq71zaFFukx773puRvNIfq939lVkFg+ISBse49Tb7P26BtUGK0K3EM wjhg== X-Gm-Message-State: AOPr4FVny2JozKisOOQliRLxvt+KYYGZDVSr73sr1fnE2JBblfwtBqgkJMbGxFxAhEkXow== X-Received: by 10.67.14.6 with SMTP id fc6mr24031390pad.55.1460671333769; Thu, 14 Apr 2016 15:02:13 -0700 (PDT) Received: from [192.168.100.91] ([199.231.240.59]) by smtp.gmail.com with ESMTPSA id n74sm60092262pfa.45.2016.04.14.15.02.12 (version=TLSv1/SSLv3 cipher=OTHER); Thu, 14 Apr 2016 15:02:12 -0700 (PDT) Content-Type: text/plain; charset=us-ascii Mime-Version: 1.0 (Mac OS X Mail 8.2 \(2104\)) Subject: Re: svn commit: r298002 - in head/sys: cam cam/ata cam/scsi conf dev/ahci From: "Ngie Cooper (yaneurabeya)" In-Reply-To: <201604142147.u3ELlwYo052010@repo.freebsd.org> Date: Thu, 14 Apr 2016 15:02:11 -0700 Cc: src-committers , svn-src-all@freebsd.org, svn-src-head@freebsd.org Content-Transfer-Encoding: 7bit Message-Id: References: <201604142147.u3ELlwYo052010@repo.freebsd.org> To: Warner Losh X-Mailer: Apple Mail (2.2104) X-BeenThere: svn-src-head@freebsd.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: SVN commit messages for the src tree for head/-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 14 Apr 2016 22:02:14 -0000 > On Apr 14, 2016, at 14:47, Warner Losh wrote: > > Author: imp > Date: Thu Apr 14 21:47:58 2016 > New Revision: 298002 > URL: https://svnweb.freebsd.org/changeset/base/298002 > > Log: > New CAM I/O scheduler for FreeBSD. The default I/O scheduler is the same > as before. The common scheduling bits have moved from inline code in > each of the CAM periph drivers into a library that implements the > default scheduling. > > In addition, a number of rate-limiting and I/O preference options can > be enabled by adding CAM_IOSCHED_NETFLIX to your config file. A number > of extra stats are also maintained. CAM_IOSCHED_NETFLIX isn't on by > default because it uses a separate BIO_READ and BIO_WRITE queue, so > doesn't honor BIO_ORDERED between these two types of operations. We > already didn't honor it for BIO_DELETE, and we don't depend on > BIO_ORDERED between reads and writes anywhere in the system (it is > currently used with BIO_FLUSH in ZFS to make sure some writes are > complete before others start and as a poor-man's soft dependency in > one place in UFS where we won't be issuing READs until after the > operation completes). However, out of an abundance of caution, it > isn't enabled by default. > > Plus, this also brings in NCQ TRIM support for those SSDs that support > it. A black list is also provided for known rogues that use NCQ trim > as an excuse to corrupt the drive. It was difficult to separate out > into a separate commit. > > This code has run in production at Netflix for over a year now. > > Sponsored by: Netflix, Inc > Differential Revision: https://reviews.freebsd.org/D4609 I left some comments in the CR. Thanks, -Ngie