Re: NFE setting manually to 1000baseT and half duplex
Wojciech Puchar wrote: Even if you do have hardware that supports half-duplex gigabit ethernet on both ends, the need to do carrier extension for any frame shorter than 512 bytes so that CSMA/CD actually works on a reasonable sized cable, does horrible things to your throughput if you've got lots of small frames. (In other words, at gigabit speeds, frames smaller than 512 bytes zip down the wire so quickly that you can no longer reliably detect collisions, so the frames all get padded.) I'm having trouble wrapping my head around any circumstances other than horribly, horribly broken hardware or software where half-duplex would increase your performance over full-duplex. actually there are no gigabit devices incapable of full-duplex. I would certainly hope so; I can't see much of a market for gigabit ethernet devices that can't do full-duplex. (I'm a touch confused, however, by your phrasing that as if you're rebutting something I wrote.) --Jon Radel smime.p7s Description: S/MIME Cryptographic Signature
Re: NFE setting manually to 1000baseT and half duplex
Even if you do have hardware that supports half-duplex gigabit ethernet on both ends, the need to do carrier extension for any frame shorter than 512 bytes so that CSMA/CD actually works on a reasonable sized cable, does horrible things to your throughput if you've got lots of small frames. (In other words, at gigabit speeds, frames smaller than 512 bytes zip down the wire so quickly that you can no longer reliably detect collisions, so the frames all get padded.) I'm having trouble wrapping my head around any circumstances other than horribly, horribly broken hardware or software where half-duplex would increase your performance over full-duplex. actually there are no gigabit devices incapable of full-duplex. ethernet hardware I've ever touched has been incapable of doing half-duplex when it's being used at gigabit speeds. The specs for doing it exist more for theoretical completeness than out of practical utility. See, for example http://www.intel.com/network/connectivity/resources/doc_library/white_papers/solutions/copper_guide/gig_over_copper.htm at 10Gbit/s specs dropped half-duplex and collision detection at all. ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "[EMAIL PROTECTED]"
Re: NFE setting manually to 1000baseT and half duplex
Gelsema, P (Patrick) - FreeBSD wrote: Hi List, I am using the nfe driver on Freebsd 7.0R and I am unable to change the NIC driver manually to 1000baseT with half-duplex. I believe I am not getting the max out of my network connection and want to see if changing the duplex will help. Even if you do have hardware that supports half-duplex gigabit ethernet on both ends, the need to do carrier extension for any frame shorter than 512 bytes so that CSMA/CD actually works on a reasonable sized cable, does horrible things to your throughput if you've got lots of small frames. (In other words, at gigabit speeds, frames smaller than 512 bytes zip down the wire so quickly that you can no longer reliably detect collisions, so the frames all get padded.) I'm having trouble wrapping my head around any circumstances other than horribly, horribly broken hardware or software where half-duplex would increase your performance over full-duplex. That said, most (an imprecise way saying "every time I've looked this has been the case, but I generally no longer bother looking") gigabit ethernet hardware I've ever touched has been incapable of doing half-duplex when it's being used at gigabit speeds. The specs for doing it exist more for theoretical completeness than out of practical utility. See, for example http://www.intel.com/network/connectivity/resources/doc_library/white_papers/solutions/copper_guide/gig_over_copper.htm for a discussion on this and related topics. My suggestion would be to let both sides auto-detect if they're both capable of gigabit ethernet. --Jon Radel smime.p7s Description: S/MIME Cryptographic Signature
Re: NFE setting manually to 1000baseT and half duplex
Erik Trulsson wrote: (IIRC a switch or NIC that is set to auto-negotiate, but where the negotiation fails (possibly because the other end is not set to auto-negotiate) will usually revert to 10Mbps/half-duplex, i.e. the original, slowest, Ethernet speed.) 100Mb half-duplex is the default setting in this sort of mismatch. It will 'sort of' work, but you'll find performance is terrible and there will be significant amounts of packet loss. Note too that 1Gb speeds require both sides to be set to autonegotiate -- it's part of the standard for supporting those speeds, so that in the event of transmission difficulties the connection can be gracefully degraded rather than just ceasing to work at all. There's a lot of received wisdom around that wiring down connection speeds is a good idea. That may have been the case 5 or more years ago, when there were certainly some combinations of NIC / network switch manufacturer that just wouldn't negotiate correctly, but now that 1Gb/s capability is pretty much standard such incompatibilities are rare. Nowadays, for best results, auto-negotiate. Cheers, Matthew -- Dr Matthew J Seaman MA, D.Phil. 7 Priory Courtyard Flat 3 PGP: http://www.infracaninophile.co.uk/pgpkey Ramsgate Kent, CT11 9PW signature.asc Description: OpenPGP digital signature
Re: NFE setting manually to 1000baseT and half duplex
On Sun, Jun 08, 2008 at 11:39:28AM +0200, Gelsema, P (Patrick) - FreeBSD wrote: > On Sun, June 8, 2008 00:49, Michael Toth wrote: > > Hi, > > You should be doing > > # ifconfig nfe0 10.202.77.110 media 1000baseTX<--- note the 'X' > > > > > > Thanks, tried this but same error. > > hulk# ifconfig nfe0 10.202.77.110 media 1000baseTX > ifconfig: SIOCSIFMEDIA (media): Device not configured > > hulk$ man nfe > The nfe driver supports the following media types: > > autoselect Enable autoselection of the media type and options. > > 10baseT/UTP Set 10Mbps operation. > > 100baseTXSet 100Mbps (Fast Ethernet) operation. > > 1000baseTSet 1000Mbps (Gigabit Ethernet) operation (recent models > only). > > The nfe driver supports the following media options: > > half-duplex Force half duplex operation. > > full-duplex Force full duplex operation. > > Also for some strange reason I lost a couple of ip aliases and my default > route whilst trying to change the media and mediaopt. > > I start to wonder if the combination 1000baseT and half duplex is > possible. However setting the NIC manually to 1000baseT doesnt work > either. IF set to autoselect it does negotiate to 1000baseT as I can see > on the switch. If you try to force the NIC to use full-/half-duplex, then you will need to force the other end of the connection (i.e. the switch) to the same setting (most cheap switches do not provide any way of forcing this.) Having one end set to auto-negotiation, while the other is forced to a specific setting will usually not work very well. (IIRC a switch or NIC that is set to auto-negotiate, but where the negotiation fails (possibly because the other end is not set to auto-negotiate) will usually revert to 10Mbps/half-duplex, i.e. the original, slowest, Ethernet speed.) -- Erik Trulsson [EMAIL PROTECTED] ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "[EMAIL PROTECTED]"
Re: NFE setting manually to 1000baseT and half duplex
On Sun, June 8, 2008 00:49, Michael Toth wrote: > Hi, > You should be doing > # ifconfig nfe0 10.202.77.110 media 1000baseTX<--- note the 'X' > > Thanks, tried this but same error. hulk# ifconfig nfe0 10.202.77.110 media 1000baseTX ifconfig: SIOCSIFMEDIA (media): Device not configured hulk$ man nfe The nfe driver supports the following media types: autoselect Enable autoselection of the media type and options. 10baseT/UTP Set 10Mbps operation. 100baseTXSet 100Mbps (Fast Ethernet) operation. 1000baseTSet 1000Mbps (Gigabit Ethernet) operation (recent models only). The nfe driver supports the following media options: half-duplex Force half duplex operation. full-duplex Force full duplex operation. Also for some strange reason I lost a couple of ip aliases and my default route whilst trying to change the media and mediaopt. I start to wonder if the combination 1000baseT and half duplex is possible. However setting the NIC manually to 1000baseT doesnt work either. IF set to autoselect it does negotiate to 1000baseT as I can see on the switch. Thanks Patrick > > > Gelsema, P (Patrick) - FreeBSD wrote: >> Hi List, >> >> I am using the nfe driver on Freebsd 7.0R and I am unable to change the >> NIC driver manually to 1000baseT with half-duplex. I believe I am not >> getting the max out of my network connection and want to see if changing >> the duplex will help. >> >> hulk# ifconfig nfe0 10.202.77.110 media 100baseTX >> hulk# ifconfig nfe0 >> nfe0: flags=8843 metric 0 mtu >> 1500 >> options=8 >> ether 00:18:f3:9f:f1:b4 >> inet6 fe80::218:f3ff:fe9f:f1b4%nfe0 prefixlen 64 scopeid 0x2 >> inet 10.202.77.113 netmask 0xff00 broadcast 10.202.77.255 >> inet 10.202.77.114 netmask 0xff00 broadcast 10.202.77.255 >> inet 10.202.77.76 netmask 0xff00 broadcast 10.202.77.255 >> inet 192.168.0.10 netmask 0xff00 broadcast 192.168.0.255 >> inet 192.168.1.10 netmask 0xff00 broadcast 192.168.1.255 >> inet 10.202.77.110 netmask 0xff00 broadcast 10.255.255.255 >> media: Ethernet 100baseTX (1000baseTX ) >> status: active >> >> Why between () the 1000baseTX? Is that the actual speed? The maximum >> speed? >> >> hulk# ifconfig nfe0 10.202.77.110 media 1000baseT >> ifconfig: SIOCSIFMEDIA (media): Device not configured >> >> man nfe says this is possible. >> >> hulk# ifconfig nfe0 10.202.77.110 media autoselect >> hulk# ifconfig nfe0 >> nfe0: flags=8843 metric 0 mtu >> 1500 >> options=8 >> ether 00:18:f3:9f:f1:b4 >> inet6 fe80::218:f3ff:fe9f:f1b4%nfe0 prefixlen 64 scopeid 0x2 >> inet 10.202.77.114 netmask 0xff00 broadcast 10.202.77.255 >> inet 10.202.77.76 netmask 0xff00 broadcast 10.202.77.255 >> inet 192.168.0.10 netmask 0xff00 broadcast 192.168.0.255 >> inet 192.168.1.10 netmask 0xff00 broadcast 192.168.1.255 >> inet 10.202.77.110 netmask 0xff00 broadcast 10.255.255.255 >> media: Ethernet autoselect (1000baseTX ) >> status: active >> >> hulk# ifconfig nfe0 mediaopt half-duplex >> No errors but cant see if it works. >> >> Question is, why cant I just do the following; >> hulk# ifconfig nfe0 media 1000baseT mediaopt half-duplex >> >> pciconf -lv >> [EMAIL PROTECTED]:0:7:0:class=0x068000 card=0x82341043 >> chip=0x03ef10de >> rev=0xa2 hdr=0x00 >> vendor = 'Nvidia Corp' >> device = 'MCP61 Ethernet' >> class = bridge >> >> hulk# uname -a >> FreeBSD hulk.superhero.nl 7.0-RELEASE FreeBSD 7.0-RELEASE #1: Sun Feb 24 >> 14:37:26 CET 2008 >> [EMAIL PROTECTED]:/usr/obj/usr/src/sys/GENERIC >> amd64 >> hulk# >> >> Thanks and regards, >> >> Patrick >> ___ >> freebsd-questions@freebsd.org mailing list >> http://lists.freebsd.org/mailman/listinfo/freebsd-questions >> To unsubscribe, send any mail to >> "[EMAIL PROTECTED]" >> > ___ > freebsd-questions@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-questions > To unsubscribe, send any mail to > "[EMAIL PROTECTED]" > ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "[EMAIL PROTECTED]"
Re: NFE setting manually to 1000baseT and half duplex
Hi, You should be doing # ifconfig nfe0 10.202.77.110 media 1000baseTX<--- note the 'X' Gelsema, P (Patrick) - FreeBSD wrote: Hi List, I am using the nfe driver on Freebsd 7.0R and I am unable to change the NIC driver manually to 1000baseT with half-duplex. I believe I am not getting the max out of my network connection and want to see if changing the duplex will help. hulk# ifconfig nfe0 10.202.77.110 media 100baseTX hulk# ifconfig nfe0 nfe0: flags=8843 metric 0 mtu 1500 options=8 ether 00:18:f3:9f:f1:b4 inet6 fe80::218:f3ff:fe9f:f1b4%nfe0 prefixlen 64 scopeid 0x2 inet 10.202.77.113 netmask 0xff00 broadcast 10.202.77.255 inet 10.202.77.114 netmask 0xff00 broadcast 10.202.77.255 inet 10.202.77.76 netmask 0xff00 broadcast 10.202.77.255 inet 192.168.0.10 netmask 0xff00 broadcast 192.168.0.255 inet 192.168.1.10 netmask 0xff00 broadcast 192.168.1.255 inet 10.202.77.110 netmask 0xff00 broadcast 10.255.255.255 media: Ethernet 100baseTX (1000baseTX ) status: active Why between () the 1000baseTX? Is that the actual speed? The maximum speed? hulk# ifconfig nfe0 10.202.77.110 media 1000baseT ifconfig: SIOCSIFMEDIA (media): Device not configured man nfe says this is possible. hulk# ifconfig nfe0 10.202.77.110 media autoselect hulk# ifconfig nfe0 nfe0: flags=8843 metric 0 mtu 1500 options=8 ether 00:18:f3:9f:f1:b4 inet6 fe80::218:f3ff:fe9f:f1b4%nfe0 prefixlen 64 scopeid 0x2 inet 10.202.77.114 netmask 0xff00 broadcast 10.202.77.255 inet 10.202.77.76 netmask 0xff00 broadcast 10.202.77.255 inet 192.168.0.10 netmask 0xff00 broadcast 192.168.0.255 inet 192.168.1.10 netmask 0xff00 broadcast 192.168.1.255 inet 10.202.77.110 netmask 0xff00 broadcast 10.255.255.255 media: Ethernet autoselect (1000baseTX ) status: active hulk# ifconfig nfe0 mediaopt half-duplex No errors but cant see if it works. Question is, why cant I just do the following; hulk# ifconfig nfe0 media 1000baseT mediaopt half-duplex pciconf -lv [EMAIL PROTECTED]:0:7:0:class=0x068000 card=0x82341043 chip=0x03ef10de rev=0xa2 hdr=0x00 vendor = 'Nvidia Corp' device = 'MCP61 Ethernet' class = bridge hulk# uname -a FreeBSD hulk.superhero.nl 7.0-RELEASE FreeBSD 7.0-RELEASE #1: Sun Feb 24 14:37:26 CET 2008 [EMAIL PROTECTED]:/usr/obj/usr/src/sys/GENERIC amd64 hulk# Thanks and regards, Patrick ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "[EMAIL PROTECTED]" ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "[EMAIL PROTECTED]"
NFE setting manually to 1000baseT and half duplex
Hi List, I am using the nfe driver on Freebsd 7.0R and I am unable to change the NIC driver manually to 1000baseT with half-duplex. I believe I am not getting the max out of my network connection and want to see if changing the duplex will help. hulk# ifconfig nfe0 10.202.77.110 media 100baseTX hulk# ifconfig nfe0 nfe0: flags=8843 metric 0 mtu 1500 options=8 ether 00:18:f3:9f:f1:b4 inet6 fe80::218:f3ff:fe9f:f1b4%nfe0 prefixlen 64 scopeid 0x2 inet 10.202.77.113 netmask 0xff00 broadcast 10.202.77.255 inet 10.202.77.114 netmask 0xff00 broadcast 10.202.77.255 inet 10.202.77.76 netmask 0xff00 broadcast 10.202.77.255 inet 192.168.0.10 netmask 0xff00 broadcast 192.168.0.255 inet 192.168.1.10 netmask 0xff00 broadcast 192.168.1.255 inet 10.202.77.110 netmask 0xff00 broadcast 10.255.255.255 media: Ethernet 100baseTX (1000baseTX ) status: active Why between () the 1000baseTX? Is that the actual speed? The maximum speed? hulk# ifconfig nfe0 10.202.77.110 media 1000baseT ifconfig: SIOCSIFMEDIA (media): Device not configured man nfe says this is possible. hulk# ifconfig nfe0 10.202.77.110 media autoselect hulk# ifconfig nfe0 nfe0: flags=8843 metric 0 mtu 1500 options=8 ether 00:18:f3:9f:f1:b4 inet6 fe80::218:f3ff:fe9f:f1b4%nfe0 prefixlen 64 scopeid 0x2 inet 10.202.77.114 netmask 0xff00 broadcast 10.202.77.255 inet 10.202.77.76 netmask 0xff00 broadcast 10.202.77.255 inet 192.168.0.10 netmask 0xff00 broadcast 192.168.0.255 inet 192.168.1.10 netmask 0xff00 broadcast 192.168.1.255 inet 10.202.77.110 netmask 0xff00 broadcast 10.255.255.255 media: Ethernet autoselect (1000baseTX ) status: active hulk# ifconfig nfe0 mediaopt half-duplex No errors but cant see if it works. Question is, why cant I just do the following; hulk# ifconfig nfe0 media 1000baseT mediaopt half-duplex pciconf -lv [EMAIL PROTECTED]:0:7:0:class=0x068000 card=0x82341043 chip=0x03ef10de rev=0xa2 hdr=0x00 vendor = 'Nvidia Corp' device = 'MCP61 Ethernet' class = bridge hulk# uname -a FreeBSD hulk.superhero.nl 7.0-RELEASE FreeBSD 7.0-RELEASE #1: Sun Feb 24 14:37:26 CET 2008 [EMAIL PROTECTED]:/usr/obj/usr/src/sys/GENERIC amd64 hulk# Thanks and regards, Patrick ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "[EMAIL PROTECTED]"
