Networking help

[Shamus_McFartfinger]

Guys (and experts in particular), I'm after some help with networking. What I need to know is how to increase throughput speed over a network (if it's possible) by decreasing packet collisions (if there are any). Will a dedicated server on a domain alleviate packet collisions? If I need to run a server, what the hell is my gigabit switch doing? Afterall, it's supposed to route packets efficiently. Kirk, I'm looking in your direction. Any help? Anyone?

[kirk1701™]

Hay Shamus, Not sure exactly what your asking yet?

 

 

Seriously, if your using 802.3 which is ethernt the following rules apply.

Carrier Sense, Multiple Access/Collision Detection: CSMA/CD

? Carrier Sense: The examining of the cable by the node to see if cable is busy before transmitting.

? Multiple Access: All machines on the network have equal access and contend for bandwidth.

? Collision Detection: If there is a collision, the NIC detects and resends the data.

 

A dedicated server is not going to decrease collisions anymore/any less then just networking the computers up through a switch on a workgroup.

 

Also keep in mind the NIC might be 10/100 and not 10/1000 which I would think is gigabit ethernet. I really haven't had a use for or played with the gigabit ethernet, hell not even sure if there is a difference just seen my motherboard has two onboard NIC's and one is GiGabit. So even though your switch is Gigabit you might be limited by the NIC only being 10/100, thats a off the wall guess now also

[Shamus_McFartfinger]

That's what I suspected. I had a debate with an expert yesterday (I'm only a dumb forklift driver) regarding this very topic. All of my PCs have gigabit NICs. They connect to a 16-port gigabit switch (a DLink DGS-1016D if that matters) and my speeds across the network suck. On a good day, maybe 25megs/sec. Usually less. Obviously, network traffic, CPU, HDs and all that other crap has an effect on throughput. Trouble is that I outfitted these things under the impression that I'd get blistering network speeds, read/write speeds of HDs dependent. Even copying from a high speed RAID drive to a SATA drive (both running in AMD64s) doesn't give me the performance I expected. Is it a case of "stiff shit" or can the performance be optimised? Can something be tweaked? Opinions? Abuse?

[kirk1701™]

OK shamus keeping with basic troubleshooting how long are your CAT5 cables from your workstations to the hub?

 

Remember 802.3 is limited to 100 meter segment lengths before a repeater is needed.

[LIGHTNING UK!]

Out of interest, have you done speed tests with a simple crossover cable between your two AMD64 machines? You know, just to see what they're able to achieve without anything else causing problems.

 

Having just tested mine (going via some netgear gigabit switch), I also get about 26.5mB/sec (according ot DU Meter).

 

Weird thing is, when I start to copy a large file, it does a few seconds at 46mB/sec before going down to that ~26 speed.

[dontasciime]

up your cat cable to at least 6 for a test between 2 comps using 10/100/1000.

 

would be best on 2 of the same nics configured, jumbo same etc.

 

i might get some cat 6 or 7 cable and test both my a7v8x gigalan out, both same broadcom 10/100/1000, as i need to know what speeds i could get, i am quite happy with the speed i get using 10/100 side of the gigalan @11MEG sec,(100) especially compared to wireless which i tried in all it's guises and hated speedwise.

Edited October 22, 2005 by dontasciime

[dontasciime]

if using 2000 you could try this

 

the parameters would be #maxcmds# The range is 0 - 255 and the 15 is the deafult value

 

#maxthreads# should be set to the same value as maxcmds

 

You could also increase the value of the #maxcollectioncount# This value represents the buffer for character-mode named pipe writes.

16 is default , you can enter 0-65535

 

I used this briefly when i used 2000 for about 4 months, i got this info a while ago and came across it tonight again, and re did the reg file, though i am usign xp, i edited my reg then exported it..

 

it increases the buffers, that are reserved for network performance, so was meant to increase throughput.

 

reg file

 

 

if anyone downloads it, can you tell me if it says it is a reg file or a winamp file. i think my file associations are screwed up.

 

edit changed it to a rar file.

Edited October 23, 2005 by dontasciime

[cornholio7]

says win amp here dontasciime

[Shamus_McFartfinger]

OK shamus keeping with basic troubleshooting how long are your CAT5 cables from your workstations to the hub?

 

Remember 802.3 is limited to 100 meter segment lengths before a repeater is needed.

 

Sorry for the delay. Been busy as hell for the last couple of days...........

 

 

You're talking about attenuation. That's packet loss, not packet collision. Nice try though. That's not the problem. Any other ideas?

[Shamus_McFartfinger]

Out of interest, have you done speed tests with a simple crossover cable between your two AMD64 machines? You know, just to see what they're able to achieve without anything else causing problems.

 

Having just tested mine (going via some netgear gigabit switch), I also get about 26.5mB/sec (according ot DU Meter).

 

Weird thing is, when I start to copy a large file, it does a few seconds at 46mB/sec before going down to that ~26 speed.

 

I haven't because it's such a pain in the arse to climb around behind my desk with leads and shit everywhere. I don't suppose I really have a choice though, huh? I'll have a crack at it later (just finished work an hour ago). I get the same sort of speeds you do. I'll try a crossover later and get back to you.

[dontasciime]

So what cable are you using ? cat 5 is no good, cat5e is kinda up to gigalan specs but can be bettered, ie cat 6 "but" with rj45 is also not upto the full specs of cat 6. Which if i am reading right is a new connector, need to read a bit more about this.

 

I am going to buy some cat6 with rj45 as thats what my equipment has and test it in a couple of days when it gets delivered, i,ll test it between 2 machine using same gigalan, using my existing cat5e cable, then with the cat6 and let you know if there is any difference.

 

And maybe someone that knows more about cat 6 full specs can tell us if it is indeed a new fitting.

[Shamus_McFartfinger]

I use cat6 here. I replaced my leads when I bought the switch. Just checked my speeds using a crossover cable and they were the same as using my switch. Odd. I thought it would be faster. *shrug*

 

That regkey above, wouldn't it also work with XP? Pipelines are pipelines afterall. Have you noticed any performance gains?

[Shamus_McFartfinger]

Just added that key to the registry on 2 machines and changed the values of all to FF. No performance gain though. Sigh.

[dontasciime]

when i ran 2000 for a short time, i used it as i seemed to be getting poor performance, it seemd to make things a little better, but you know what computers are like something can seem to make a difference when it could have been something else.

 

just thought i would post it up incase you saw some benefit from it, im not sure if xp handles things different, as i think it does, something i read on ms site, but trying to find info on ms site is hit n miss.

Edited October 23, 2005 by dontasciime

[Shamus_McFartfinger]

Thanks anyway. Looks like I'll be Googling to try and find out what's limiting it's speed. How can a person easily get 5MB/sec using TBase100 and not get 40MB/sec when there's 10x the bandwidth? It's a strange one.

[Shamus_McFartfinger]

Just did a quick test with a tool I found called NETIO. http://freshmeat.net/projects/netio/

 

There's something peculiar about all this.

 

[kirk1701™]

Shamus

 

I see netBios failed????

 

I know your not using WINS so just for kicks, try disabling NetBios over TCP/IP and let us know.

[dontasciime]

check the advanced on your netowrk card, and see if like mine there is option to optimize for CPU or throughput..

 

Have you also tried changing it from AUTO to some of the options regarding speed full duplex etc

[Shamus_McFartfinger]

Shamus

 

I see netBios failed????

 

I know your not using WINS so just for kicks, try disabling NetBios over TCP/IP and let us know.

 

The failure you see above is just me not inputting the correct command for Netio. If I disable NETBIOS, my network dissapears.

[Shamus_McFartfinger]

check the advanced on your netowrk card, and see if like mine there is option to optimize for CPU or throughput..

 

I found a setting like this the other day. Changing it from CPU to THROUGHPUT just killed the connection. (Which I thought was weird).

 

Have you also tried changing it from AUTO to some of the options regarding speed full duplex etc

 

Not as yet. I'm reluctant to change too much incase I screw it up. A default config (with a button) for these things would be nice. I have found out something though, it's bloody hard to get a definitive answer on how fast gigabit should actually be across a LAN. I'm wondering if I can tweak the packet sizes somewhere. It's gotta be in the registry. 8k packets would give me 40MB/sec according to that Netio thingy.

Edited October 24, 2005 by Shamus_McFartfinger