Ok I get horrific lag in all multiplayer LFS server. It's not gfx based so don't tell me the difference between FPS and latency.

Most obvious symptom is that all the cars on the server randomly teleport 20 feet (my client projecting the last known input I presume) or so, and then back, and then teleport, and so on. I have unblocked the relevant ports on the router, and my local firewall (I am usually running through a linux server, but this occurs even straight thru the router).
I have reinstalled mobo drivers, LAN drivers, Windows (I *really* want this to work) and tried most of the (somewhat bizarre) fixes on the forum for similar probs. Unfortunately most of the people complaining of 'lag' are actually getting a CPU clock desync, which this is not.

I am open to all suggestions, as I can't race & have now been told to stay off even the city driving servers until it's fixed.

-Try using a wired connection if you're using wireless.
-Linux server _and_ a router? Are you at home or office If you aren't the only person using the connection, try at a time when there are less people using it. Also, check with your network admin if anything is being throttled.
-Close P2P programs and any other server software.
-Go to command prompt and do a traceroute to a few common sites and check that latencies generally are good.
-If all else fails, talk to your ISP.

Is it possible your internet connection is slow?

Also when running LFS, make sure you're not running other programs in the background.

Quote from NotAnIllusion :

-Try using a wired connection if you're using wireless.
-Linux server _and_ a router? Are you at home or office If you aren't the only person using the connection, try at a time when there are less people using it. Also, check with your network admin if anything is being throttled.
-Close P2P programs and any other server software.
-Go to command prompt and do a traceroute to a few common sites and check that latencies generally are good.
-If all else fails, talk to your ISP.

I'm at home, my old man has quite a gnarly setup, but at night mine is the only PC on and I'm going straight into the router.

no p2p or other programs running, done some traceroute with mostly good results, will try more LFS server addresses & see what happens.

I'm pretty convinced this is a random LFS bug, as searching on the forums here I found one or two people describing the same thing, but all of those threads fizzled out with no answer.

"Mostly good results" with a traceroute? What does that mean? How's the packet loss etc?

If LFS always lags, without exception, then it is more likely your computer itself that's causing it. Try using another computer (that has no spyware, or too many resource hogs or other crap) on the same internet line.

Quote from Breizh :

"Mostly good results" with a traceroute? What does that mean? How's the packet loss etc?

If LFS always lags, without exception, then it is more likely your computer itself that's causing it. Try using another computer (that has no spyware, or too many resource hogs or other crap) on the same internet line.

"mostly good" means 0% packet loss to all the UK servers I've pinged/tracert so far, and on tracert to all UK servers I get under 100ms (usually under 40ms) per jump.

There is no spyware, malware, p2p software or anything like that on this PC, I reinstalled windows 2 days ago (and I run a fairly tight ship anyway).

I've never had problems of this nature I couldn't solve before, my dad works as a software engineer so I'm fairly computer literate.


EDIT: One of the most common explanations for this type of problem is the ISP shaping packets to block p2p software. I'm with zen however, and

Quote :

Please note: Zen Internet do NOT perform any traffic shaping of any protocol.

so it isn't that either.

well they said they dont shape protocols but what if they shape ports?
As far as I know shaping is done on ports and doesnt matter protocol you use.

Maybe I am too picky but I know well how ISP playing "games" with home users.

Had my experience with some of the previous providers.Traffic and testing was fine over standart ports but when it went to ports over 1000 which are well known for some non standard usuage they were shaping these ports like mad because they were trying to throttle p2p connection which LFS is NOT.

I'm pretty sure they mean no traffic shaping of any kind, did a quick search on their forum & they seem adamant that there's none.

Here are some threads from this forum with similar problems;

http://www.lfsforum.net/showth ... t=25493&highlight=lag

http://www.lfsforum.net/showth ... t=23566&highlight=lag (not quite the same, I can see other cars they can't see me)

http://www.lfsforum.net/showth ... t=23344&highlight=lag - the link in top post to a video is more or less exactly what I see online

None of the solutions posted are actually for this problem, they're for CPU clock desync etc. The ones with this prob have never been answered. Most promising I've seen is someone who reccommended guaranteeing 66% of upload bandwidth to LFS, I will try this later. (though I have tested at night with no other PCs/programs running in the house & it's the same)

I have somewhere on my PC at home a program which you can use to test your connection with your mate.

You can choose what ever port you want even simulate LFS port it use and see if you are getting shaped on the higher ports or not.

I will post later when I will get back to home.

This can be a really stupid question, does lfs freeze like every 4.5 sec or any type of freezeing at all and also type of windows do you have?

Quote from rc10racer :

This can be a really stupid question, does lfs freeze like every 4.5 sec or any type of freezeing at all and also type of windows do you have?

I run Windows XP Pro service pack 2
Offline, perfectly smooth

Online, I do get judders every 10-20s but that seems to be when all the netgraphs peak. A lot of people who had the 4-5s stutter problem were falsely diagnosing a cpu clock desync as lag, but I'm 99% certain that's not the case here.

All of those were fixed by really random solutions (reinstalling mobo drivers etc) most of which I've tried, to no avail. My old man thinks it may be someone else traffic shaping along the route, but I'm not so sure.

Take your pc, as-is, to a friend's and see if it happens there too. If it does, it's something to do with your pc, if it doesn't, it's something in between your pc and the game servers. If it's the case of the latter, get a cheapo dsl/cable modem (alternatively, if you can, put the router into a sort of modem only mode, or DMZ your pc) so that there isn't even a router connecting you to the internet and test again. If that solves it, replace router I guess, if not then you might be SOL

Erk

Turns out, I reinstalled my 'acpi PC' to a standard PC and it's sorted it out, I thought it can't possibly be that as people were reporting stutter every few seconds and not horrible, sould crushing lag.

So if anyone has this prob, try that. How embarrasing.



Thanks to everyone who helped

EDIT: Celebration was premature, the server is now in sync (no more +timeinit messages), but I am still getting lag spikes every 20-30s, where the netgraph fills to max (all bars) for a few seconds, then drops back down to 'normal'.

Cars are now much less jittery, but still teleporting a foot or so here & there. I will fraps tomorrow.