Hello,
my configuration is
kernel GENERIC
em0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> metric 0 mtu 1500
options=18b<RXCSUM,TXCSUM,VLAN_MTU,VLAN_HWCSUM,TSO4>
ether 00:19:d1:0f:1c:18
inet 86.49.14.16 netmask 0xffffff00 broadcast 86.49.14.255
media: Ethernet autoselect (100baseTX <full-duplex>)
status: active
and standard "open" ipfw firewall and
natd -u -s -m -d -dynamic -n em0
I experience very slow TCP upload from this host - cca 50kbps.
I have some debug prints in kernel (mostly in ip_output and ipfw log)
and I see:
1/ outgoing packet appears in ip_output with ip_len 2924 and
m->pkthdr.csum_flags=1
2/ is diverted by firewall
3/ Packet appears immediately again in ip_output with ip_len 2924 and
m->pkthdr.csum_flags=1
4/ Packet is accepted by firewall and dropped by ip_output with error 40
EMSGSIZE
5/ After cca 0.4s (tcp retransmit timeout?) new packet appears in
ip_output with ip_len 1488 and m->pkthdr.csum_flags=1
6/ is successfully diverted and accepted by ipfw and sent to wire.
7/ after tcp ack is received new packet appears in ip_output with ip_len
2924 and everything repeats
Packets are not changed by natd, beacause have src address of em0.
nat
Upload has normal speed (512kbps) if
I unset TSO on interface OR set net.inet.tcp.tso=0 OR (strange thing)
delete ipfw divert rule
If necessary I will collect and send more info.
vita
On Nov 29, 2007 11:21 PM, Vitezslav Novy <vnovy@vnovy.net> wrote:> Hello, > > my configuration is > > kernel GENERIC > > em0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> metric 0 mtu 1500 > options=18b<RXCSUM,TXCSUM,VLAN_MTU,VLAN_HWCSUM,TSO4> > ether 00:19:d1:0f:1c:18 > inet 86.49.14.16 netmask 0xffffff00 broadcast 86.49.14.255 > media: Ethernet autoselect (100baseTX <full-duplex>) > status: active > > and standard "open" ipfw firewall and > natd -u -s -m -d -dynamic -n em0 > > I experience very slow TCP upload from this host - cca 50kbps. > I have some debug prints in kernel (mostly in ip_output and ipfw log) > and I see: > > 1/ outgoing packet appears in ip_output with ip_len 2924 and > m->pkthdr.csum_flags=1 > 2/ is diverted by firewall > 3/ Packet appears immediately again in ip_output with ip_len 2924 and > m->pkthdr.csum_flags=1 > 4/ Packet is accepted by firewall and dropped by ip_output with error 40 > EMSGSIZE > 5/ After cca 0.4s (tcp retransmit timeout?) new packet appears in > ip_output with ip_len 1488 and m->pkthdr.csum_flags=1 > 6/ is successfully diverted and accepted by ipfw and sent to wire. > 7/ after tcp ack is received new packet appears in ip_output with ip_len > 2924 and everything repeats > > > Packets are not changed by natd, beacause have src address of em0. > nat > > > Upload has normal speed (512kbps) if > I unset TSO on interface OR set net.inet.tcp.tso=0 OR (strange thing) > delete ipfw divert rule > > If necessary I will collect and send more info.TSO is silly at 100Mb, turn it off :) Jack
Jack Vogel wrote:> On Nov 29, 2007 11:21 PM, Vitezslav Novy <vnovy@vnovy.net> wrote: >> Hello, >> >> my configuration is >> >> kernel GENERIC >> >> em0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> metric 0 mtu 1500 >> options=18b<RXCSUM,TXCSUM,VLAN_MTU,VLAN_HWCSUM,TSO4> >> ether 00:19:d1:0f:1c:18 >> inet 86.49.14.16 netmask 0xffffff00 broadcast 86.49.14.255 >> media: Ethernet autoselect (100baseTX <full-duplex>) >> status: active >> >> and standard "open" ipfw firewall and >> natd -u -s -m -d -dynamic -n em0 >> >> I experience very slow TCP upload from this host - cca 50kbps. >> I have some debug prints in kernel (mostly in ip_output and ipfw log) >> and I see: >> >> 1/ outgoing packet appears in ip_output with ip_len 2924 and >> m->pkthdr.csum_flags=1 >> 2/ is diverted by firewall >> 3/ Packet appears immediately again in ip_output with ip_len 2924 and >> m->pkthdr.csum_flags=1 >> 4/ Packet is accepted by firewall and dropped by ip_output with error 40 >> EMSGSIZE >> 5/ After cca 0.4s (tcp retransmit timeout?) new packet appears in >> ip_output with ip_len 1488 and m->pkthdr.csum_flags=1 >> 6/ is successfully diverted and accepted by ipfw and sent to wire. >> 7/ after tcp ack is received new packet appears in ip_output with ip_len >> 2924 and everything repeats >> >> >> Packets are not changed by natd, beacause have src address of em0. >> nat >> >> >> Upload has normal speed (512kbps) if >> I unset TSO on interface OR set net.inet.tcp.tso=0 OR (strange thing) >> delete ipfw divert rule >> >> If necessary I will collect and send more info. > > TSO is silly at 100Mb, turn it off :)When this was reported before I asked why does the driver allow it, if it is "silly" and causes so many problems? Why not just disable it by default if the link is 100Mb? Kris