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{
    "id": 815096,
    "url": "http://patchwork.ozlabs.org/api/1.2/covers/815096/?format=api",
    "web_url": "http://patchwork.ozlabs.org/project/netdev/cover/20170918190733.26272-1-edumazet@google.com/",
    "project": {
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        "url": "http://patchwork.ozlabs.org/api/1.2/projects/7/?format=api",
        "name": "Linux network development",
        "link_name": "netdev",
        "list_id": "netdev.vger.kernel.org",
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    "msgid": "<20170918190733.26272-1-edumazet@google.com>",
    "list_archive_url": null,
    "date": "2017-09-18T19:07:26",
    "name": "[net-next,0/7] net: speedup netns create/delete time",
    "submitter": {
        "id": 13357,
        "url": "http://patchwork.ozlabs.org/api/1.2/people/13357/?format=api",
        "name": "Eric Dumazet",
        "email": "edumazet@google.com"
    },
    "mbox": "http://patchwork.ozlabs.org/project/netdev/cover/20170918190733.26272-1-edumazet@google.com/mbox/",
    "series": [
        {
            "id": 3713,
            "url": "http://patchwork.ozlabs.org/api/1.2/series/3713/?format=api",
            "web_url": "http://patchwork.ozlabs.org/project/netdev/list/?series=3713",
            "date": "2017-09-18T19:07:26",
            "name": "net: speedup netns create/delete time",
            "version": 1,
            "mbox": "http://patchwork.ozlabs.org/series/3713/mbox/"
        }
    ],
    "comments": "http://patchwork.ozlabs.org/api/covers/815096/comments/",
    "headers": {
        "Return-Path": "<netdev-owner@vger.kernel.org>",
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        "X-Received": "by 10.84.216.78 with SMTP id f14mr29729706plj.394.1505761657946; \n\tMon, 18 Sep 2017 12:07:37 -0700 (PDT)",
        "From": "Eric Dumazet <edumazet@google.com>",
        "To": "\"David S . Miller\" <davem@davemloft.net>",
        "Cc": "netdev <netdev@vger.kernel.org>,\n\t\"Eric W . Biederman\" <ebiederm@xmission.com>,\n\tEric Dumazet <edumazet@google.com>, Eric Dumazet <eric.dumazet@gmail.com>",
        "Subject": "[PATCH net-next 0/7] net: speedup netns create/delete time",
        "Date": "Mon, 18 Sep 2017 12:07:26 -0700",
        "Message-Id": "<20170918190733.26272-1-edumazet@google.com>",
        "X-Mailer": "git-send-email 2.14.1.690.gbb1197296e-goog",
        "Sender": "netdev-owner@vger.kernel.org",
        "Precedence": "bulk",
        "List-ID": "<netdev.vger.kernel.org>",
        "X-Mailing-List": "netdev@vger.kernel.org"
    },
    "content": "When rate of netns creation/deletion is high enough,\nwe observe softlockups in cleanup_net() caused by huge list\nof netns and way too many rcu_barrier() calls.\n\nThis patch series does some optimizations in kobject,\nand add batching to tunnels so that netns dismantles are\nless costly.\n\nIPv6 addrlabels also get a per netns list, and tcp_metrics\nalso benefit from batch flushing.\n\nThis gives me one order of magnitude gain.\n(~50 ms -> ~5 ms for one netns create/delete pair)\n\nTested:\n\nfor i in `seq 1 40`\ndo\n (for j in `seq 1 100` ; do  unshare -n /bin/true >/dev/null ; done) &\ndone\nwait ; grep net_namespace /proc/slabinfo\n\nBefore patch series :\n\n$ time ./add_del_unshare.sh\nnet_namespace        116    258   5504    1    2 : tunables    8    4    0 : slabdata    116    258      0\n\nreal\t3m24.910s\nuser\t0m0.747s\nsys\t0m43.162s\n\nAfter :\n$ time ./add_del_unshare.sh\nnet_namespace        135    291   5504    1    2 : tunables    8    4    0 : slabdata    135    291      0\n\nreal\t0m22.117s\nuser\t0m0.728s\nsys\t0m35.328s\n\nEric Dumazet (7):\n  kobject: add kobject_uevent_net_broadcast()\n  kobject: copy env blob in one go\n  kobject: factorize skb setup in kobject_uevent_net_broadcast()\n  ipv6: addrlabel: per netns list\n  tcp: batch tcp_net_metrics_exit\n  ipv6: speedup ipv6 tunnels dismantle\n  ipv4: speedup ipv6 tunnels dismantle\n\n include/net/ip_tunnels.h |  3 +-\n include/net/netns/ipv6.h |  5 +++\n lib/kobject_uevent.c     | 95 ++++++++++++++++++++++++++----------------------\n net/ipv4/ip_gre.c        | 22 +++++------\n net/ipv4/ip_tunnel.c     | 13 +++++--\n net/ipv4/ip_vti.c        |  7 ++--\n net/ipv4/ipip.c          |  7 ++--\n net/ipv4/tcp_metrics.c   | 14 ++++---\n net/ipv6/addrlabel.c     | 81 +++++++++++++++--------------------------\n net/ipv6/ip6_gre.c       |  8 ++--\n net/ipv6/ip6_tunnel.c    | 20 +++++-----\n net/ipv6/ip6_vti.c       | 23 +++++++-----\n net/ipv6/sit.c           |  9 +++--\n 13 files changed, 159 insertions(+), 148 deletions(-)"
}