wierd dsl performance with -CURRENT

[Kenneth Culver]

> > Transferring anything through the BSD NAT box shows the same performance
> > issues, as well as transferring directly from BSD to the DSL modem on both
> > of my BSD machines. Using windows or the mac directly connected to the DSL
> > modem shows the normal bandwidth capability. I know the hardware isn't the
> > problem, both of the BSD boxes are totally different. If you think it
> > matters I can send the specs too.
> >
> >
> > Ken
>
> Can you do a
> 'netstat -s -p tcp >> tcpstats' before and after the transfer?
>
> This should tell us if there were retransmits etc.  It could be a
> difference in minimum rtt values or a congestion issue that results in
> timeout for our stack but some other recovery mechanism with other stacks.
>

Here is the output of the netstat before and after transferring "kern.flp"
for FreeBSD 5.1:

tcp:
        28727 packets sent
                13954 data packets (3760142 bytes)
                363 data packets (19245 bytes) retransmitted
                8 data packets unnecessarily retransmitted
                0 resends initiated by MTU discovery
                9842 ack-only packets (1036 delayed)
                0 URG only packets
                0 window probe packets
                2703 window update packets
                1892 control packets
        35600 packets received
                14218 acks (for 3760605 bytes)
                761 duplicate acks
                0 acks for unsent data
                23779 packets (18905861 bytes) received in-sequence
                41 completely duplicate packets (9457 bytes)
                0 old duplicate packets
                0 packets with some dup. data (0 bytes duped)
                1220 out-of-order packets (1657153 bytes)
                0 packets (0 bytes) of data after window
                0 window probes
                3 window update packets
                7 packets received after close
                1 discarded for bad checksum
                0 discarded for bad header offset fields
                0 discarded because packet too short
        789 connection requests
        679 connection accepts
        0 bad connection attempts
        0 listen queue overflows
        1427 connections established (including accepts)
        1466 connections closed (including 335 drops)
                17 connections updated cached RTT on close
                17 connections updated cached RTT variance on close
                1 connection updated cached ssthresh on close
        7 embryonic connections dropped
        13345 segments updated rtt (of 13120 attempts)
        565 retransmit timeouts
                4 connections dropped by rexmit timeout
        0 persist timeouts
                0 connections dropped by persist timeout
        0 keepalive timeouts
                0 keepalive probes sent
                0 connections dropped by keepalive
        1216 correct ACK header predictions
        15958 correct data packet header predictions
        691 syncache entries added
                34 retransmitted
                28 dupsyn
                1 dropped
                679 completed
                0 bucket overflow
                0 cache overflow
                8 reset
                4 stale
                0 aborted
                0 badack
                0 unreach
                0 zone failures
        0 cookies sent
        0 cookies received

This is after:

tcp:
        29493 packets sent
                14005 data packets (3761865 bytes)
                363 data packets (19245 bytes) retransmitted
                8 data packets unnecessarily retransmitted
                0 resends initiated by MTU discovery
                10238 ack-only packets (1040 delayed)
                0 URG only packets
                0 window probe packets
                3020 window update packets
                1894 control packets
        36688 packets received
                14269 acks (for 3762329 bytes)
                761 duplicate acks
                0 acks for unsent data
                24759 packets (20268809 bytes) received in-sequence
                41 completely duplicate packets (9457 bytes)
                0 old duplicate packets
                0 packets with some dup. data (0 bytes duped)
                1298 out-of-order packets (1770089 bytes)
                0 packets (0 bytes) of data after window
                0 window probes
                3 window update packets
                7 packets received after close
                1 discarded for bad checksum
                0 discarded for bad header offset fields
                0 discarded because packet too short
        790 connection requests
        679 connection accepts
        0 bad connection attempts
        0 listen queue overflows
        1428 connections established (including accepts)
        1467 connections closed (including 335 drops)
                17 connections updated cached RTT on close
                17 connections updated cached RTT variance on close
                1 connection updated cached ssthresh on close
        7 embryonic connections dropped
        13396 segments updated rtt (of 13171 attempts)
        565 retransmit timeouts
                4 connections dropped by rexmit timeout
        0 persist timeouts
               0 connections dropped by persist timeout
        0 keepalive timeouts
                0 keepalive probes sent
                0 connections dropped by keepalive
        1221 correct ACK header predictions
        16914 correct data packet header predictions
        691 syncache entries added
                34 retransmitted
                28 dupsyn
                1 dropped
                679 completed
                0 bucket overflow
                0 cache overflow
                8 reset
                4 stale
                0 aborted
                0 badack
                0 unreach
                0 zone failures
        0 cookies sent
        0 cookies received

Thanks...

Could this be something my ISP did that causes a problem for FreeBSD and
not the other OS's?

Ken