Multplayer desync

from Sins Forums

Hey guys,

 

Well Kiernyc and I still play Sins from time to time after all these years, and occasionally we get desyncs (or "the space time continuum is messed up again" as we like to call it). We do get these when uses mods and when not using mods, the latest time it happened we were using a slightly modified Distant Stars mod. We are both using the latest version of Diplomacy with Entrenchment. We both saved it as different names, so we can upload those if need be. Please let me know what other files you might need to help troubleshoot this problem. It's a pretty annoying issue as we only find out once one of us complains about something happening (ie pirates) and the other says "what pirates?"

 

Anyways let me know what files and any other information you might need. Thanks,

T

technical
10,634 views 9 replies
Reply #1 from Sins Forums Top

Yes it is quite annoying and strange. Especially since we don't know when it desynced and for all we know we were playing different games for hours! Suggestions would be helpful and nice!

Reply #2 from Sins Forums Top

I never once got desynced. Try turning off auto-save, after a big battle we usually pause and manually save. If it is just the 2 of you, we dont use ICO, we use IP connect, better comp should always host.

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Reply #3 from Sins Forums Top

Quoting Admiral_Kiernyc, reply 1
Yes it is quite annoying and strange. Especially since we don't know when it desynced and for all we know we were playing different games for hours! Suggestions would be helpful and nice!
End of Admiral_Kiernyc's quote

 

Yeah and what makes it even more confusing is that our moves are the same, it's just the AI that get desynced (I think)

Reply #4 from Sins Forums Top

Quoting Thrawn2787, reply 3
Yeah and what makes it even more confusing is that our moves are the same, it's just the AI that get desynced (I think)
End of Thrawn2787's quote

LOL. Is the AI using a separate computer? Computers desync, not the AI. I am pretty sure the hosts computer controls the AI and transmits the info to the clients.

Reply #5 from Sins Forums Top

Quoting myfist0, reply 4
The hosts computer controls the AI and transmits the info to the clients.
End of myfist0's quote

I don't know if this holds true for LAN, but on ICO the Dev journals make it sound that every computer is simulating the AI, but since each computer gets the exact some commands and generates the exact same random numbers, the AI acts in the same way on each computer. You get desyncs when for some reason this doesn't happen.

Either way, the AI is certainly the biggest thing that desyncs can screw up. Games with only human players can still be effected, but as you noticed its your commands are still read correctly in a desync so its not as obvious.

Reply #6 from Sins Forums Top

Thank for the clarification GoaFan. I did edit that line and added "I am pretty sure" just before you posted.

That does seem like a rather goofy way to sync the game, like it's guaranteed to fail unless you are playing with the exact same computers.

Reply #7 from Sins Forums Top

The whole Dev Journal is a must read for anyone dealing with desyncs, but here is the part I was referencing.

Unlike MMO's, FPS's or many other multiplayer games, in an RTS there is no master server who has a final say in the current state of the game. You may notice in something like World of Warcraft that your avatar suddenly gets his position corrected. What is happening there is your local simulation of the WoW universe has the character moving a certain way, but then the master server says that is incorrect and tells him to reposition himself. You were out of sync with the boss and the boss set you in your place. For an RTS game its far too impractical (in many different respects) to have a master server checking over everybody so we rely on determinism to make sure every stays in sync. Determinism is about making sure everything happens in the exact same way. If you can guarantee everything happens in the same way, you don't need a master server telling everyone what the results are and you don't have to send much information between the player's computers.
End of quote

Reply #8 from Sins Forums Top

Odd indeed. It seemed like in the last game that desynced that the AI gave the pirates a mission (I didn't know they could do that) that was headed for Kiernycs home. He was complaining because he thought it was  a raid at one of his planets that was undefended, but the pirates kept going so he thought it was a mission from an AI. While he was talking about the pirates I kept looking for them and didn't find anything, so we realized there was a desync

 

But the other times this has happened similar things happen. Like I say help or thats a big fleet and Kiernyc says what fleet? We've also tested it out, and human moves still work, it's just the AI that's out of sync. I wonder how that handles damage? My whole fleet could be blown up by an AI but if the game was out of sync... would my fleet just combust on kiernyc's end or would it still be there I wonder?

Reply #9 from Sins Forums Top

To help track this down, we need save games from each player (preferably the last auto-save before the desync occurred), dxdiags from each machine, and game record files.  Please zip these up with as much info as you have as to what was going on before the desync took place and do not use mods.  (Sorting out desyncs is hard enough without trying to figure out what stuff a mod is doing that may cause something else to happen.) ;)

If you can reproduce with the latest version of Diplomacy without mods, then send your files to sinssupport@stardock.com.

 

Thanks!