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{
    "id": 41363,
    "url": "http://patches.dpdk.org/api/covers/41363/?format=api",
    "web_url": "http://patches.dpdk.org/cover/41363/",
    "project": {
        "id": 1,
        "url": "http://patches.dpdk.org/api/projects/1/?format=api",
        "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": "<20180621132414.39047-1-david.hunt@intel.com>",
    "date": "2018-06-21T13:24:06",
    "name": "[v2,0/8] examples/vm_power: 100% Busy Polling",
    "submitter": {
        "id": 342,
        "url": "http://patches.dpdk.org/api/people/342/?format=api",
        "name": "David Hunt",
        "email": "david.hunt@intel.com"
    },
    "mbox": "http://patches.dpdk.org/cover/41363/mbox/",
    "series": [
        {
            "id": 193,
            "url": "http://patches.dpdk.org/api/series/193/?format=api",
            "web_url": "http://patches.dpdk.org/project/dpdk/list/?series=193",
            "date": "2018-06-21T13:24:10",
            "name": "examples/vm_power: 100% Busy Polling",
            "version": 2,
            "mbox": "http://patches.dpdk.org/series/193/mbox/"
        }
    ],
    "comments": "http://patches.dpdk.org/api/covers/41363/comments/",
    "headers": {
        "Return-Path": "<dev-bounces@dpdk.org>",
        "References": "<20180607073705.32895-2-david.hunt@intel.com>",
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        "X-IronPort-AV": "E=Sophos;i=\"5.51,252,1526367600\"; d=\"scan'208\";a=\"68839744\"",
        "From": "David Hunt <david.hunt@intel.com>",
        "List-Post": "<mailto:dev@dpdk.org>",
        "List-Help": "<mailto:dev-request@dpdk.org?subject=help>",
        "X-ExtLoop1": "1",
        "X-BeenThere": "dev@dpdk.org",
        "Message-Id": "<20180621132414.39047-1-david.hunt@intel.com>",
        "X-Original-To": "patchwork@dpdk.org",
        "Received": [
            "from [92.243.14.124] (localhost [127.0.0.1])\n\tby dpdk.org (Postfix) with ESMTP id 39B9F1BB4D;\n\tThu, 21 Jun 2018 15:25:17 +0200 (CEST)",
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        ],
        "X-Mailer": "git-send-email 2.17.1",
        "Sender": "\"dev\" <dev-bounces@dpdk.org>",
        "Subject": "[dpdk-dev] [PATCH v2 0/8] examples/vm_power: 100% Busy Polling",
        "Precedence": "list",
        "Date": "Thu, 21 Jun 2018 14:24:06 +0100",
        "List-Archive": "<http://mails.dpdk.org/archives/dev/>",
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        "List-Subscribe": "<https://mails.dpdk.org/listinfo/dev>,\n\t<mailto:dev-request@dpdk.org?subject=subscribe>",
        "Cc": "david.hunt@intel.com",
        "List-Id": "DPDK patches and discussions <dev.dpdk.org>",
        "Delivered-To": "patchwork@dpdk.org",
        "In-Reply-To": "<20180607073705.32895-2-david.hunt@intel.com>",
        "List-Unsubscribe": "<https://mails.dpdk.org/options/dev>,\n\t<mailto:dev-request@dpdk.org?subject=unsubscribe>",
        "To": "dev@dpdk.org",
        "X-Amp-Result": "SKIPPED(no attachment in message)",
        "Errors-To": "dev-bounces@dpdk.org"
    },
    "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\n[1/8] examples/vm_power: add check for port count\n[2/8] examples/vm_power: add core list parameter\n[3/8] examples/vm_power: add oob monitoring functions\n[4/8] examples/vm_power: allow greater than 64 cores\n[5/8] examples/vm_power: add thread for oob core monitor\n[6/8] examples/vm_power: add port-list to command line\n[7/8] examples/vm_power: add branch ratio policy type\n[8/8] examples/vm_power: add cli args to guest app"
}