lkml.org 
[lkml]   [2009]   [Apr]   [28]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    From
    SubjectRe: [PATCH] poll: Avoid extra wakeups in select/poll
    Eric Dumazet a écrit :
    > Christoph Lameter a écrit :
    >> On Tue, 28 Apr 2009, Eric Dumazet wrote:
    >>
    >>> The one that did improved your udpping 'bench' :)
    >>>
    >>> http://git2.kernel.org/?p=linux/kernel/git/davem/net-2.6.git;a=commitdiff;h=bf368e4e70cd4e0f880923c44e95a4273d725ab4
    >> Well yes that is git2p1. The measurements that we took showed not much of
    >> an effect as you see.
    >>
    >
    > It depends of coalescing parameters of NIC.
    >
    > BNX2 interrupts first handle TX completions, then RX events.
    > So If by the
    >

    Sorry for the previous message...

    If by the time interrupt comes to the host, TX was handled right before RX event,
    the extra wakeup is not a problem, because incoming frame will be delivered into
    socket queue right before awaken thread tries to pull it.

    On real workloads (many incoming/outgoing frames), then avoiding extra wakeups is
    a win, regardless of coalescing parameters and cpu affinities...

    On uddpping, I had prior to the patch about 49000 wakeups per second,
    and after patch about 26000 wakeups per second (matches number of incoming
    udp messages per second)

    --
    To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
    the body of a message to majordomo@vger.kernel.org
    More majordomo info at http://vger.kernel.org/majordomo-info.html
    Please read the FAQ at http://www.tux.org/lkml/

    \
     
     \ /
      Last update: 2009-04-28 23:17    [W:0.020 / U:125.236 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site