Network Latency
#1
My network needs are, of course, WoW related, and I am interested in ways of reducing network latency, specifically TCP latency since TCP is what WoW uses.

Typically I had been seeing in game latency a bit less than 200 ms. Recently (as in the last couple of weeks) my latency has spiked much higher, and I have been having frequent disconnects -- "frequent" as in every few minutes -- one of which resulted in a tragic death.

In reading up on the problem, some say the disconnects are the result of ISP "traffic shaping", a euphemism (to get all political about this) for what the U.S. Republican controlled House of Representatives did to Internet consumers. Who, for the most part, are at the mercy of monopolies.

Since moving to Finland is not a viable option for me at the moment, I am exploring technical solutions for reducing latency. Years ago on NT and XP I tweaked network settings to try to get low ping. But since the Windows 7 era I had pretty much figured Bill knows best. Which may have been naive.

Last night I implemented what is called the "TcpAckFrequency fix". I do not know who gets original credit for the idea, as it is not recent and it is all over the web. I added two registry values, TcpAckFrequency and TCPNoDelay, to the key for my ethernet adapter. Keys for ethernet adapters are found under:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\Tcpip\Parameters\Interfaces\

Each adapter has a GUI. Find the GUI for the adapter being used and insert new DWORD values for TcpAckFrequency and TCPNoDelay. Set both values to 1.

After applying the fix I had significantly lower latency as measured in game. I was going to say latency never got above 50 ms. But then I saw it spike twice to 52 ms. Still, much, much better than what I had before.

Now I'm wondering if there is anything else that would make an improvement in latency, either hardware or software. Does anyone know these days whether the ethernet adapter makes a difference? In olden times I would always go with Intel, as other vendors' adapters usually had problems. My server has an Intel adapter in it to this day. My hunch is that ethernet adapters are not yet a commodity, and that the brand and model still matter. However for my last few motherboards I have just used what's on the motherboard, currently a Realtek.

In looking at the current crop of about to be announced AMD 3+ motherboads it looks like one of Asus' offerings has an Intel NIC. Last time I bought Intel NIC's the list price was around $260. Bigfoot Networks makes a gaming specific NIC that sells for about $90. Some reports say Bigfoot helps with WoW. Most say it's not worth it.

What NIC's do other people use? Has anyone tried Bigfoot? Any other network suggestions?


Edit: I wonder if the cable modem makes a difference? Some say bridged connections reduce latency, but that would not only require a DOCSIS 3.0 modem but also require paying Comcast for the privilege.

I read tonight Comcast offers a small discount for the aged, but for that I have about two years left to go. I don't think WoW requires the bandwidth a bridged connection offers anyway. I used to play quite happily on a dial-up connection, till the ISP went out of business.
"I may be old, but I'm not dead."
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#2
Not on WoW traffic (which isn't throttled here in Netherlands(me)-Belgium-France(servers)), but on bittorent some clients support traffic encryption and obfuscation so it doesn't look like bittorent traffic. It will then not suffer from idiot ISP's who use throttling on such traffic. Like on your perfectly legal WoW patches. Smile
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#3
I actually got very upset with my ISP provider recently and was even contemplating sueing them!

I had been noticing my bandwidth dropping significantly during the evenings - some Netflix movies woudln't even play because the on screen prompt said my bandwidth was too low! During this period, I was getting around 1.5 mbps up to 3 mbps. I called my ISP provider and told them I was paying for 20 mbps so what gives? They told me that if I had read the fine print, that I was actually guarenteed 15 mbps with a variable 5 mbps speedboost, whatever the hell that means. Anyways, I told them my speed was still not high enough. The sent out a tech who made some adjustments and then left. Problems persisted. Several techs (I believe at least six more times I called them for this same issue) and several weeks later, I finally get the ISP's direct speed tester. I find out that during peak hours, the speed to my ISP server itself maintains an average of 15-20 mbps, however the speed going out to the rest of the net is reduced to 1.5-3 mbps. Hummm... so during peak hours, the same $$$, my ISP is reducing the speed going out to the rest of the net! So I complained to their senior tech who assured me this was not happening. I then got really upset and told them - and this is the truth - that they were illegially restricting my internet speed during peak hours, that I was paying for 15 mbps guarenteed to the internet, not just to their servers. I never heard from them again. I still had the same problem a few weeks after, and this was the time I considered filing a lawsuit against my ISP, but for whatever reason now, the problem seems to be gone.

Thought this site had a spell checker! I'm on my work computer and am totally restricted... cannot use MS Word, google spell check locked out! Wish there was one on this site right now.
"The true value of a human being is determined primarily by the measure and the sense in which he has attained liberation from the self." -Albert Einsetin
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#4
I use TraceRT to view the route to the server and where any delays occur. Also, I check to see how long name lookup to the DNS takes, since that can add quite a bit of time too. There are ways to optimize your throughput depending on your NIC and your ISP's network settings. I was just messing around testing some ideas on my NIC here and had to go into 'SAFE MODE" to undo them, so beware and make sure you are ready for a debugging session.

Packet shaping when done right is actually a good thing for customers, and ensures everyone gets equal access to bandwidth. An ISP has a limited maximum bandwidth to distribute, and without some shaping the performance each person experiences would be extremely variable. It would be great until a bunch of cable users all decided to stream the big game, or download some big files. Then, us transactional users would experience long wait times for the pipe to open enough to let our few packets through.
(05-30-2011, 07:18 PM)MEAT Wrote: Thought this site had a spell checker! I'm on my work computer and am totally restricted... cannot use MS Word, google spell check locked out! Wish there was one on this site right now.
Are you using Firefox?

(Tools > Options > Advanced : General: Browsing: "Check my spelling as I type")

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