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{
    "id": 41540,
    "url": "http://patches.dpdk.org/api/covers/41540/",
    "web_url": "http://patches.dpdk.org/cover/41540/",
    "project": {
        "id": 1,
        "url": "http://patches.dpdk.org/api/projects/1/",
        "name": "DPDK",
        "link_name": "dpdk",
        "list_id": "dev.dpdk.org",
        "list_email": "dev@dpdk.org",
        "web_url": "http://core.dpdk.org",
        "scm_url": "git://dpdk.org/dpdk",
        "webscm_url": "http://git.dpdk.org/dpdk"
    },
    "msgid": "<20180626092317.11031-1-david.hunt@intel.com>",
    "date": "2018-06-26T09:23:08",
    "name": "[0/9] examples/vm_power: 100% Busy Polling",
    "submitter": {
        "id": 342,
        "url": "http://patches.dpdk.org/api/people/342/",
        "name": "Hunt, David",
        "email": "david.hunt@intel.com"
    },
    "mbox": "http://patches.dpdk.org/cover/41540/mbox/",
    "series": [
        {
            "id": 235,
            "url": "http://patches.dpdk.org/api/series/235/",
            "web_url": "http://patches.dpdk.org/project/dpdk/list/?series=235",
            "date": "2018-06-26T09:23:08",
            "name": "examples/vm_power: 100% Busy Polling",
            "version": 1,
            "mbox": "http://patches.dpdk.org/series/235/mbox/"
        }
    ],
    "comments": "http://patches.dpdk.org/api/covers/41540/comments/",
    "headers": {
        "List-Subscribe": "<https://mails.dpdk.org/listinfo/dev>,\n\t<mailto:dev-request@dpdk.org?subject=subscribe>",
        "Cc": "david.hunt@intel.com",
        "X-Original-To": "patchwork@dpdk.org",
        "Date": "Tue, 26 Jun 2018 10:23:08 +0100",
        "In-Reply-To": "<20180621132414.39047-2-david.hunt@intel.com>",
        "Precedence": "list",
        "X-BeenThere": "dev@dpdk.org",
        "References": "<20180621132414.39047-2-david.hunt@intel.com>",
        "X-Mailer": "git-send-email 2.17.1",
        "List-Archive": "<http://mails.dpdk.org/archives/dev/>",
        "To": "dev@dpdk.org",
        "X-Amp-Result": "SKIPPED(no attachment in message)",
        "Errors-To": "dev-bounces@dpdk.org",
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            "from mga04.intel.com (mga04.intel.com [192.55.52.120])\n\tby dpdk.org (Postfix) with ESMTP id 2810A1B483\n\tfor <dev@dpdk.org>; Tue, 26 Jun 2018 11:23:31 +0200 (CEST)",
            "from orsmga001.jf.intel.com ([10.7.209.18])\n\tby fmsmga104.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384;\n\t26 Jun 2018 02:23:30 -0700",
            "from silpixa00399952.ir.intel.com (HELO\n\tsilpixa00399952.ger.corp.intel.com) ([10.237.223.64])\n\tby orsmga001.jf.intel.com with ESMTP; 26 Jun 2018 02:23:29 -0700"
        ],
        "From": "David Hunt <david.hunt@intel.com>",
        "List-Help": "<mailto:dev-request@dpdk.org?subject=help>",
        "X-ExtLoop1": "1",
        "X-Amp-File-Uploaded": "False",
        "Sender": "\"dev\" <dev-bounces@dpdk.org>",
        "List-Id": "DPDK patches and discussions <dev.dpdk.org>",
        "Subject": "[dpdk-dev] [0/9] examples/vm_power: 100% Busy Polling",
        "List-Unsubscribe": "<https://mails.dpdk.org/options/dev>,\n\t<mailto:dev-request@dpdk.org?subject=unsubscribe>",
        "Return-Path": "<dev-bounces@dpdk.org>",
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        "Delivered-To": "patchwork@dpdk.org",
        "Message-Id": "<20180626092317.11031-1-david.hunt@intel.com>",
        "X-Mailman-Version": "2.1.15"
    },
    "content": "This patch set adds the capability to do out-of-band power\nmonitoring on a system. It uses a thread to monitor the branch\ncounters in the targeted cores, and calculates the branch ratio\nif the running code.\n\nIf the branch ratop is low (0.01), then\nthe code is most likely running in a tight poll loop and doing\nnothing, i.e. receiving no packets. In this case we scale down\nthe frequency of that core.\n\nIf the branch ratio is higher (>0.01), then it is likely that\nthe code is receiving and processing packets. In this case, we\nscale up the frequency of that core.\n\nThe cpu counters are read via /dev/cpu/x/msr, so requires the\nmsr kernel module to be loaded. Because this method is used,\nthe patch set is implemented with one file for x86 systems, and\nanother for non-x86 systems, with conditional compilation in\nthe Makefile. The non-x86 functions are stubs, and do not\ncurrently implement any functionality.\n\nThe vm_power_manager app has been modified to take a new parameter\n   --core-list or -l\nwhich takes a list of cores in a comma-separated list format,\ne.g. 1,3,5-7,9, which resolvest to a core list of 1,3,5,6,7,9\nThese cores will then be enabled for oob monitoring. When the\nOOB monitoring thread starts, it reads the branch hits/miss\ncounters of each monitored core, and scales up/down accordingly.\n\nThe guest_cli app has also been modified to allow sending of a\npolicy of type BRANCH_RATIO where all of the cores included in\nthe policy will be monitored by the vm_power_manager oob thread.\n\nv2 changes:\n   * Add the guest_cli patch into this patch set, including the\n     ability to set the policy to BRANCH_RATIO.\n     http://patches.dpdk.org/patch/40742/\n   * When vm_power_manger receives a policy with type BRANCH_RATIO,\n     add the relevant cores to the monitoring thread.\n\nv3 changes:\n   * Added a command line parameter to alloe changing of the\n     default branch ratio threshold. can now use -b 0.3 or\n     --branch-ratio=0.3 to set the ratio for scaling up/down.\n\n[1/9] examples/vm_power: add check for port count\n[2/9] examples/vm_power: add core list parameter\n[3/9] examples/vm_power: add oob monitoring functions\n[4/9] examples/vm_power: allow greater than 64 cores\n[5/9] examples/vm_power: add thread for oob core monitor\n[6/9] examples/vm_power: add port-list to command line\n[7/9] examples/vm_power: add branch ratio policy type\n[8/9] examples/vm_power: add cli args to guest app\n[9/9] examples/vm_power: make branch ratio configurable"
}