Hardware requirements for dedicated server

[HornetMaX]

The high upload and low download does seem to suggest the server is doing most of the game data processing. I was hoping that the heavy data processing for each bike would be on its client end and the server just passed each bikes 'pose' and position data between clients with only race management and collision detection as overheads.

The server does very little, all the physics integration is done by each client.

The data that is sent from the server to the players is (essentially) bikes' status (position, attitude, etc) + track evolution (groove).

MaX.

[h106frp]

That's more how i expected it to be arranged.

Thinking about it i think i finally understand see where the bandwidth imbalance comes from 

So 16 bikes feed data to the 1 server but the server repeats (uploads) 15(or 16 for integrity) bikes data to 16 different clients.

So..

16 players:
So for each 16 incoming data blocks (downstream)  256 have to be sent out (upsteam) 

Scaling is harsh on the upsteam side but seems to be in line with dibu's numbers;

32 players:
So for each 32 incoming data blocks (downstream)  1024 have to be sent out (upsteam) 

Twice the number of players, 2 times the download but 4 times the data to upload.

..The above is probably gibberish but it makes me feel like i am less confused 

Had a read and apparently the reason given for poor upload bandwidth on UK cable is that they have decided that for a given copper link between user and the fibre box (docsis RF bit) most of the bandwidth will be dedicated to TV channel and media (down) streaming.

[HornetMaX]

Thinking about it i think i finally understand see where the bandwidth imbalance comes from 

Always better to think first

Had a read and apparently the reason given for poor upload bandwidth on UK cable is that they have decided that for a given copper link between user and the fibre box (docsis RF bit) most of the bandwidth will be dedicated to TV channel and media (down) streaming.

The reason is not really technical: the overall bandwidth is limited by the hardware, so one has to decide how to split it between download and upload.
The typical Joe needs much more download than upload, so here we go.

This is a bit less true today (with people using cloud storage, uploading a lot of crap to youtube etc), but was very very true in the past.

Anyway, you can look up what the A means in ADSL

MaX.

[h106frp]

Its a shame they do not let you choose how to balance your bandwidth up/down within the total bandwidth available, I probably only use a fraction of my downstream bandwidth.

Still, a small session with 10 or 12  bikes seems perfectly feasible on domestic fibre broadband .

Curious if something like a Gigabyte Brix with a Celeron dual core could be a low power host, quite cheap especially if you have some old memory and small SSD available.

[HornetMaX]

Its a shame they do not let you choose how to balance your bandwidth up/down within the total bandwidth available, I probably only use a fraction of my downstream bandwidth.

Not sure there's any technical limitation, it's probably that there's not enough people interested in that.

MaX.

[dibu]

HDD speed is not important. At least about 50 GB should be free for tracks, bikes, replays etc.


The CPU usage is quite low but always remember that only one core is used by the dedicated server. Some of the modern low power Celerons and Pentium might be underpowered (Thanks to Intel for their irritating naming ). 
Haswell-Cores like the Celeron G1840 should be ok.


RAM usage mainly depends on the replay size you need. In waiting mode a dedicated server consumes 10-50 MB depending on the track. If one or more user connects, the RAM usage will increase to  RAM in waiting mode + RAM you've choosen for replay.

Example for two dedicated servers and a replay size of 600 MB:

RAM for OS                  1,000 MB

Server1:
RAM in waiting mode        20 MB
RAM for replay                600 MB
 
Server2:
RAM in waiting mode        50 MB
RAM for replay                600 MB
                                  ------------
Total RAM needed        2,270 MB

[h106frp]

Thanks for the info on core usage. I was wary GPB might not like 'modern' processor architecture.

[HornetMaX]

Thanks for the info on core usage. I was wary GPB might not like 'modern' processor architecture.

Why would that be !? It runs fine on your main PC so ... at worst it can't really leverage on multiple cores/threads. But that just means you can probably run multiple servers on the same machine

MaX.

[h106frp]

Thanks for the info on core usage. I was wary GPB might not like 'modern' processor architecture.

Why would that be !? It runs fine on your main PC so ... at worst it can't really leverage on multiple cores/threads. But that just means you can probably run multiple servers on the same machine

MaX.

Nice idea i have a Q6600 system in bit in a drawer which would be quite quick/core, but triple host would hit the upstream bandwidth problem pretty quickly lol

I was mainly curious if a modern low power micro PC would handle simple server duty. I might set up my old dual core celeron laptop as a test platform, i do not use it for anything else these days as i have a fancy works laptop instead.

Need to get up to speed with firewalls suitable for a host - any suggested reading? I guess my routers built in firewall would be considered insufficient 

[Napalm Nick]

Quick update - 8 people on my server and Network activity is 0.6Mbps lol

[h106frp]

Thanks, that in line with dibu's figures, the problem is scaling 0.6Mbit with 8 could be 2.4Mbit with 16 players from my guesstimates earlier (no idea of fixed overheads or data packing).

Dibu's figures suggest that for 16 players its 2.0 Mbit  so it's probably not quite so severe but it is very non-linear. Twice the players = 3.33 times the upload bandwidth 

Figures seem to work out so 'simple' hosting seems possible for 12 to 16 players on a standard domestic broadband connection (fiber).

[Napalm Nick]

Thursday should be a good indicator if everyone turns up 

[Napalm Nick]

Here's a couple of perfmon screens from Thursdays race.
1st one is running two dedi servers same machine, 11 people on server 1, 1 on server 2
2nd is 13 on server 1 and server 2 shutdown.
RAM usage is interesting. This server has 4Gb with a dedicated GCard. Network useage is minimal. If we get +20 people on the server I will capture some more to see how exponential the use-age vs clients is.

You might need to DL and zoom them.
Hope it's useful.

[h106frp]

Some interesting info. The high disk usage is curious in example 2 - seems to be a bit of that going around on other threads.

Network usage seems quite light.

Has made me realize i have an issue with killernetworks drivers on my game PC, seems to generate a lot of background traffic. I will have to see if it can be removed and let windows manage the traffic.

Any opinions on Atheros killernetworks? What is it doing to generate traffic?

Picked up a used one these very cheap 



Really impressed with it, 'proper' i3 with 4GB,  a neat little machine and near silent. 

Will probably let it upgrade itself to win10 as a test platform before i configure it as a trial server.

If the missus does not grab it first as a replacement desktop i could be in business - i knew i had a problem when it was described as 'cute'  when i unpacked it though  .