Wednesday, July 25, 2007

Gigabit Ethernet Upgrade


I bought one of these 8 port switches:
TRENDnet TEG-S8 10/100/1000Mbps Gigabit Switch 8 x RJ45 8K entries per device MAC Address Table 8Kbytes per device Buffer Memory - Retail

Then I bought 2 of these:
TRENDnet TEG-S80TXE 10/20/100/200/2000Mbps Copper Gigabit Switch 8 x RJ45 4K entries per device MAC Address Table 128KB per Device Buffer Memory - Retail
These were instant $10 off and free shipping last week.

bought 5 of these:
TRENDnet TEG-PCITXR 10/ 100/ 1000/ 2000Mbps PCI Copper Gigabit Network Adapter 1 x RJ45 - Retail
but I got them at Fry's. Only $10 each regular price.
Make sure on the back of the box you look for rev 3.0 near the upc.
uses realtek rtl8169 chipset so use realtek drivers.

TRENDnet TEG-PCBUSR 32-bit Gigabit CardBus PC Card - Retail
Also got this at Fry's for only $25 regular price.
uses realtek rtl8169 chipset so use realtek drivers.

Trendnet nic drivers are over a year old (even on their site). That's ok since they just use a realtek chipset. Use these drivers instead:
look under the "RTL8110S-32/RTL8110SB(L)/RTL8169SB(L)/RTL8169SC(L)
RTL8169" section.
Find "Auto installation program (support WinXP 64/Win98SE/WinME/Win2K/WinXP ver.671))(Submission ID: 1257464)"
Then I just manually extract it, and when winxp asks for drivers I just point to the winxp subdir. I didn't run their setup.

network benchmarks:
- Network benchmark utility. It works really well. It takes hard drive throughput out of the equation. I verified results with netpersec.
receiver: pcattcp -c -r -f m
send short: pcattcp -t -f m -n 5000 %1 (%1 = machine name of receiver)
send long: pcattcp -t -f m -n 100000 %1
- here is another one iperf:

- The only thing I have setup is the first switch (TEG-S8), two of the trendnet nics, and one pc with built in gigabit nf4. I should get the other two switches today.
- First the trendnet documentation is BUNK, PURE UTTER GARBAGE AND INCORRECT!!!! So No where in the manual is there like a chart to tell you what all the lights mean on the switch. There is a speed light which is labeled 100/1000 and can be off, yellow, or green. In the back of the manual is a faq that pretty clearly states that if the light is off then you are in 10 mode, yellow is 100, and green is 1000 (had wife read it and she agrees that is what is written). That made sense to me green being the fastest, yellow means slower/caution/something wrong. Ok so I plug everything in and I notice the nf4 machine is green, but the trendnet nic machine is yellow. I'm like aw crap. In winxp it shows 1 gigabit connection but the switch shows yellow. I run ttcp tests and it confirms my fears. I'm still stuck around 85mbps. Something was wrong. The manual states you might need cat 5e or cat 6. I don't have any of that but I've heard that most of the time cat 5 is just fine. I go through about 4 other different brands of cat 5 cables I have and they all still show yellow and still stuck at around 85mbps. I even move the cable over to the nf4 machine and noticed it went from green to yellow. I'm like how can I have only one good cat 5 cable? I thought it was kind of odd but I head out to fry's and grab some cat 6. I get home and same thing. Yellow yellow yellow! Finally for kicks I decide to replace the nf4 machine with one of the new cat 6 cables. Now all ports show yellow. I run the ttcp test and I get 300mbps!
YELLOW = 1000, GREEN = 100!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
So basically I had one bad cat 5 cable and the rest were actually ok.
So yeah for the most part cat 5 should work just fine for gigabit. Right now all 3 test machines are on cat 6.
- On my low end machines (athlon xp) cpu utilization can get up to the 15-20% range which seems pretty high under full network load.
- Transfers between nf4 and trendnet are right around 300 but between the two trendnet machines it's closer to 200 one way and then down to like 150 the other. I'm not sure why there is such a big discrepancy.
- Enabling jumbo frames didn't seem to make much of a difference. Either way I set trendnet to the max of 7K and the nf4 to 9K (this is done at the driver properties level).
- I noticed zonealarm has a big impact on performance on low end machines. With it off I get 220mbps, with it on only 137mbps.
- On my original 100mbps network ttcp showed about 75-85mbps. So expect anywhere from 2-4X real world improvement.

- I tested the TEG-s80TXE switches. I got both of them in. They are metal vs plastic and feel much better built than the TEG-S8. That said performance seems about the same. Oh yeah in this model they don't even talk about the color of the lights. BTW they are flipped in this model:
green = 1000, yellow = 100!!!!
- I also installed the pc card on the laptop. I was getting crazy speeds of over 300 receiving and 125 sending. That was over about 75 ft of regular old cat 5.

Jumbo Frames:
- I get mixed results with different settings. At 7K I actually had an issue where I couldn't copy a large from (gw.dat - over 3.5gb) the laptop to the the desktop. Sending large files from the laptop would actually eventually stall and error out. Disabling it caused receiving on the laptop to fluctuate like mad (a few seconds of 250 then almost 0 then 250 then 0). Also, the fluctuations do NOT show up under ttcp. They only show up under large file copies. I can see the rate fluctuate clearly using netpersec with .25 sec updates. Setting jumbo frames to 2K seems to solve all my issues. I'm not exactly sure why though. You would think moving from the default 1.5K MTU to 2K MTU wouldn't make much of a difference. My theory is when jumbo frames is enabled in the realtek drivers it takes some other code path through those drivers. Anyways at 2K I was receiving at about 230 and sending at around 120 (real world file copy).
- So final most stable settings are: jumbo frames 2K, force speed: 1000/full duplex.

Overall you kind of get what you pay for. The switches are fine (though they do run a tad warm). On the other hand, the realtek based NICs and PC Card are a bit finicky. You have to play with them quite a bit, and just accept performance differences between machines and upstream/downstream even though they are the same motherboard and nic (with no real explanation why there is a performance difference). I hear drivers make a big difference and at least realtek is actively developing them. I hear the intel NICs are a lot better but they cost $31. In the end I got the speed I required which is to burn DVD's at 8X over the network on my laptop (need around 92mbps sustained throughput).

UPDATE: 10/10/08
For TRENDnet TEG-PCBUSR 32-bit Gigabit CardBus PC Card - Retail under vista 32bit the generic realtek drivers wouldn't work. I kept getting the dreaded network cable unplugged error. Instead go use the latest trendnet drivers which fixed all my issues:

UPDATE: 10/12/08
- So digging a bit into the documentation it would seem the TRENDnet TEG-S8 definitely does have Jumbo frame support. On the TRENDnet TEG-S80TXE I'm not so sure now though the jumbo frame testing I did above was with this switch. It seemed to make some difference when turning on the jumbo frames but I'm not sure why. I checked the documentation on the TEG-S80TXE, and I don't see any mentioning of jumbo frame support for any of the hardware revisions (I have D1).
- So for now I would say the TEG-S8 definitely does have jumo frames. It's mentioned right in the documentation: "Supports Jumbo Frame of up to 9728bytes packet size." It would seem the TEG-S80TXE does NOT have jumbo frames. Well, it looks like I'll have to move some of my switches around and redo my jumbo frames testings. Sorry for the confusion. Why would they put the better electronics in the cheaper plastic case is beyond me.
- I will say that all the switches have been very reliable and have worked fine for more than a year now.


The Angry Intern said...

how many computers do you have on your network that you need that many giga ports??

Mc said...

Are you saying that the TEG-S80TXE does support jumbo frames?