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From: "Qing Li" <qingli@speakeasy.net>
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Date: Fri, 29 Apr 2005 19:30:51 -0700
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Subject: FW: pmtu patch
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-----Original Message-----
From: Qing Li [mailto:qingli@FreeBSD.org] 
Sent: Thursday, April 28, 2005 5:36 PM
To: andre@freebsd.org
Cc: qingli@freebsd.org
Subject: pmtu patch


    Hi Andre,

    I was thinking whether we could add another variable
    in "hc_metrics" called "u_long rmx_mtu_lastupdate" and
    perhaps a new function called "tcp_hc_getmtu_update"

    When we get the ICMP PRC_MSGSIZE notification, we do

    if (((time_second() - tcp_hc_getmtu_update(&inc)) < PMTU_MIN)
        do_nothing;
    else {
      ...
    }

    If there is no suggested mtu value, instead of immediately 
    falling back to the default, or rely on the original 
    packet fragment, can we just use the mtu value in the
    host cache as the basis for the next try as in:

    else {

        <set new value for rmx_mtu_lastupdate>

        mtu = ip_next_mtu(tcp_hc_getmtu(&inc), 1);

    }

    -- Qing