Question
Answer
What is latency?
[n] The time that elapses between sending a packet and receiving a response.
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What is lag?
Lag is any combination of packet loss, high latency, and warping.
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What is tickrate?
Tickrate is used by many applications to manage its own CPU usage.
In Unreal Tournament, tickrate is the Frames per second that the server is running at. For example, a tick rate of 20 means the server is running at 20 FPS.
Serverside, each frame represents the processing of actions. So, if a server is running at 20 FPS, it is processing player movements, gun fire, objects, and etc 20 times per second (or every 50ms).
A high tick rate means the server is able to process actions faster, or more time per second. If the tickrate is too low, everything will seem jerky.
However, increasing your tick rate will not always increase server performance. It will more than likely increase CPU usage of your server, but if it is processing data fast enough already, it will not decrease ping one bit.
[Tick Rates. It is very important that admins do not alter their servers tick rates. Changing this setting can cause your server to use more CPU and overload the machine it is on. When you do this you do not smooth out play, you steal CPU from the other people on the machine and in doing so you lag the entire machine. My policy regarding tickrates is outlined in the terms of service everyone agrees to when they sign up. Please don't do this, as it makes things difficult for our techs and ruins play for the people you share your machine with.]
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What is ping?
Lets have a ping of 60 in DOS to a certain server. This means a packet of data uses 60 milliseconds to go from your super fantastic computer to the crappy tickrate 20 server in Uganda and back. In other words. Now because of the complexity of the net, this doesn't mean it uses 30ms to reach the server, and 30ms to travel back. (Asymmetric routing) Someone else will have to explain why this is so. But lets assume that this is actually the true thing this time. The data DOES use 30ms to travel from your computer to the server, and 30ms to reach your computer again. Let's put in some more numbers. The tickrate! We know that it's 50ms between each tick on server. So let's take worst case. The packet of data we send, uses 30ms to reach server. The server has just completed a tick before the data arrived, so the data has to wait for 50ms. Ok, data has waited 50ms and been processed, and now leaves the server for the client to happily enjoy. This takes another 30ms. So to add it up, the packet used 30+50+30 = 110ms to travel from client to server, be processed on server, and return to client.
Another thing that affects result is your own frame rate. Your computer will not handle data while it's busy telling the video card what to show you. A frame rate of 100fps means that it's another 1000ms/100 = 10ms between each time it can handle data.
You thought that was all? You were wrong. Again. Of course!
The DOS ping usually only sends a small packet, of like 32 bytes. If only UT sent that little! The more data, the higher the ping gets. Go ahead and try it yourself.
PING -l 32 Pings the server you choose with a 32byte packet.
Example:
C:>ping ut.online.no -l 32
Pinging ut.online.no [193.213.112.70] with 32 bytes of data:
Reply from 193.213.112.70: bytes=32 time=35ms TTL=116
Reply from 193.213.112.70: bytes=32 time=34ms TTL=116
Reply from 193.213.112.70: bytes=32 time=34ms TTL=116
Reply from 193.213.112.70: bytes=32 time=34ms TTL=116
This looks good! Now lets try with a larger packet, like 512 bytes.
PING -l 512
Example:
C:>ping ut.online.no -l 512
Pinging ut.online.no [193.213.112.70] with 512 bytes of data:
Reply from 193.213.112.70: bytes=512 time=156ms TTL=116
Reply from 193.213.112.70: bytes=512 time=155ms TTL=116
Reply from 193.213.112.70: bytes=512 time=155ms TTL=116
Reply from 193.213.112.70: bytes=512 time=155ms TTL=116
Oops, it suddenly didn't look too good anymore right? But then again, I only have a fancy 64kbit isdn line. Mileage may vary depending on your connection.
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What is netspeed?
What is netspeed good for? What does it do?
The netspeed decides how much data you want to send to the server each second. A netspeed of 5000 will try to send 5000 bytes of data each second. And yes, for the smart ones out there that already guessed it, netspeed of 13690 will send 13690 bytes per second. Also, it tells the server how much data you want to receive each second. The servers seem to not allow going under 2000, clients have a minimum of 500.
Some interesting aspect with the netspeed, is that it limits your frame rate. Your maximum expected frame rate online with netspeed 5000 is 5000/64 = 78fps. You should not get more, you will often get less. So why /64 you ask? Well, it's kinda simple. Each time your computer does an update, it sends about 64 bytes of data. So the great dudes at epic thought, let's do netspeed/64 and limit frame rate that way, so the client does not exceed netspeed bytes sent pr second.
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What is DOS Ping vs Game Ping?
Lets have a ping of 60 in DOS to a certain server. This means a packet of data uses 60 milliseconds to go from your super fantastic computer to the crappy tickrate 20 server in Uganda and back. In other words. Now because of the complexity of the net, this doesn't mean it uses 30ms to reach the server, and 30ms to travel back. (Asymmetric routing) Someone else will have to explain why this is so. But lets assume that this is actually the true thing this time. The data DOES use 30ms to travel from your computer to the server, and 30ms to reach your computer again. Let's put in some more numbers. The tickrate! We know that it's 50ms between each tick on server. So let's take worst case. The packet of data we send, uses 30ms to reach server. The server has just completed a tick before the data arrived, so the data has to wait for 50ms. Ok, data has waited 50ms and been processed, and now leaves the server for the client to happily enjoy. This takes another 30ms. So to add it up, the packet used 30+50+30 = 110ms to travel from client to server, be processed on server, and return to client.
Another thing that affects result is your own frame rate. Your computer will not handle data while it's busy telling the video card what to show you. A frame rate of 100fps means that it's another 1000ms/100 = 10ms between each time it can handle data.
You thought that was all? You were wrong. Again. Of course :)
The DOS ping usually only sends a small packet, of like 32 bytes. If only UT sent that little :) The more data, the higher the ping gets. Go ahead and try it yourself.
PING -1 32 Pings the server you choose with a 32byte packet.
Example:
C:>ping ut.online.no -l 32
Pinging ut.online.no [193.213.112.70] with 32 bytes of data:
Reply from 193.213.112.70: bytes=32 time=35ms TTL=116
Reply from 193.213.112.70: bytes=32 time=34ms TTL=116
Reply from 193.213.112.70: bytes=32 time=34ms TTL=116
Reply from 193.213.112.70: bytes=32 time=34ms TTL=116
This looks good! Now lets try with a larger packet, like 512 bytes.
PING -1 512
Example:
C:>ping ut.online.no -l 512
Pinging ut.online.no [193.213.112.70] with 512 bytes of data:
Reply from 193.213.112.70: bytes=512 time=156ms TTL=116
Reply from 193.213.112.70: bytes=512 time=155ms TTL=116
Reply from 193.213.112.70: bytes=512 time=155ms TTL=116
Reply from 193.213.112.70: bytes=512 time=155ms TTL=116
Oops, it suddenly didn't look too good anymore right? But then again, I only have a fancy 64kbit ISDN line. Mileage may vary depending on your connection.
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My server is down. What do I do?
My servers are set to automatically restart if they crash. However, if the server will not restart here are some steps to take:
If your server is down, first check to see what may have changed in your configuration files.
To be honest, servers very rarely crash themselves, and I never take them down without a very good reason.
If you have recently made changes to your config, then try to undo them, and try again.
If you have not made any changes, ping your server using a DOS ping:
start > run > ping my.ip -t
If it times out, then the machine your server is on is probably down outright. Wait fifteen minutes to see if it comes back up, as I may be performing maintenance on the machine. If it does not come back up, CONTACT ME
When your server is down, you are more than welcome to call me as well:
512-244-7881
The most important thing is to get in touch with me, even if you use other support methods to resolve the problem because it will allow me to track your support history, and will let me know if I need to take action to improve your server's stability or performance.
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