kern.hz and single tcp connection throughput

From: Urmas Lett (urmas.lett_at_eenet.ee)
Date: 02/28/05

  • Next message: sam wun: "ping: sendto: Host is down on vrrp IP." 
    Date: Mon, 28 Feb 2005 13:21:37 +0200
To: freebsd-net@freebsd.org

    Hello,

    I was playing with iperf over ~500km empty gigabit link.

    FreeBSD 5.3-STABLE
    kern.hz="100" (default)

    root@test2:~# iperf -c x.x.x.x
    ------------------------------------------------------------
    Client connecting to x.x.x.x, TCP port 5001
    TCP window size: 32.5 KByte (default)
    ------------------------------------------------------------
    [ 3] local y.y.y.y port 56931 connected with x.x.x.x port 5001
    [ ID] Interval Transfer Bandwidth
    [ 3] 0.0-10.0 sec 28.8 MBytes 24.1 Mbits/sec

    root@test2:~# iperf -c x.x.x.x -w 64k
    ------------------------------------------------------------
    Client connecting to x.x.x.x, TCP port 5001
    TCP window size: 65.0 KByte (WARNING: requested 64.0 KByte)
    ------------------------------------------------------------
    [ 3] local y.y.y.y port 57926 connected with x.x.x.x port 5001
    [ ID] Interval Transfer Bandwidth
    [ 3] 0.0-10.0 sec 28.3 MBytes 23.6 Mbits/sec

    root@test2:~# iperf -c x.x.x.x -w 128k
    ------------------------------------------------------------
    Client connecting to x.x.x.x, TCP port 5001
    TCP window size: 129 KByte (WARNING: requested 128 KByte)
    ------------------------------------------------------------
    [ 3] local y.y.y.y port 64330 connected with x.x.x.x port 5001
    [ ID] Interval Transfer Bandwidth
    [ 3] 0.0-10.0 sec 29.0 MBytes 24.2 Mbits/sec

    root@test2:~# iperf -c x.x.x.x -w 256k
    ------------------------------------------------------------
    Client connecting to x.x.x.x, TCP port 5001
    TCP window size: 257 KByte (WARNING: requested 256 KByte)
    ------------------------------------------------------------
    [ 3] local y.y.y.y port 55575 connected with x.x.x.x port 5001
    [ ID] Interval Transfer Bandwidth
    [ 3] 0.0-10.1 sec 31.2 MBytes 26.0 Mbits/sec

    root@test2:~# iperf -c x.x.x.x -w 512k
    ------------------------------------------------------------
    Client connecting to x.x.x.x, TCP port 5001
    TCP window size: 513 KByte (WARNING: requested 512 KByte)
    ------------------------------------------------------------
    [ 3] local y.y.y.y port 59043 connected with x.x.x.x port 5001
    [ ID] Interval Transfer Bandwidth
    [ 3] 0.0-10.2 sec 30.0 MBytes 24.7 Mbits/sec

    ============================================================
    kern.hz="1000"

    root@test2:~# iperf -c x.x.x.x
    ------------------------------------------------------------
    Client connecting to x.x.x.x, TCP port 5001
    TCP window size: 32.5 KByte (default)
    ------------------------------------------------------------
    [ 3] local y.y.y.y port 61402 connected with x.x.x.x port 5001
    [ ID] Interval Transfer Bandwidth
    [ 3] 0.0-10.0 sec 44.5 MBytes 37.3 Mbits/sec

    root@test2:~# iperf -c x.x.x.x -w 64k
    ------------------------------------------------------------
    Client connecting to x.x.x.x, TCP port 5001
    TCP window size: 65.0 KByte (WARNING: requested 64.0 KByte)
    ------------------------------------------------------------
    [ 3] local y.y.y.y port 62718 connected with x.x.x.x port 5001
    [ ID] Interval Transfer Bandwidth
    [ 3] 0.0-10.0 sec 87.9 MBytes 73.7 Mbits/sec

    root@test2:~# iperf -c x.x.x.x -w 128k
    ------------------------------------------------------------
    Client connecting to x.x.x.x, TCP port 5001
    TCP window size: 129 KByte (WARNING: requested 128 KByte)
    ------------------------------------------------------------
    [ 3] local y.y.y.y port 50571 connected with x.x.x.x port 5001
    [ ID] Interval Transfer Bandwidth
    [ 3] 0.0-10.0 sec 169 MBytes 142 Mbits/sec

    root@test2:~# iperf -c x.x.x.x -w 256k
    ------------------------------------------------------------
    Client connecting to x.x.x.x, TCP port 5001
    TCP window size: 257 KByte (WARNING: requested 256 KByte)
    ------------------------------------------------------------
    [ 3] local y.y.y.y port 61072 connected with x.x.x.x port 5001
    [ ID] Interval Transfer Bandwidth
    [ 3] 0.0-10.0 sec 305 MBytes 255 Mbits/sec

    root@test2:~# iperf -c x.x.x.x -w 512k
    ------------------------------------------------------------
    Client connecting to x.x.x.x, TCP port 5001
    TCP window size: 513 KByte (WARNING: requested 512 KByte)
    ------------------------------------------------------------
    [ 3] local y.y.y.y port 62887 connected with x.x.x.x port 5001
    [ ID] Interval Transfer Bandwidth
    [ 3] 0.0-10.5 sec 451 MBytes 362 Mbits/sec

    _______________________________________________
    freebsd-net@freebsd.org mailing list
    http://lists.freebsd.org/mailman/listinfo/freebsd-net
    To unsubscribe, send any mail to "freebsd-net-unsubscribe@freebsd.org"

  • Next message: sam wun: "ping: sendto: Host is down on vrrp IP."

    Relevant Pages