MP downloaded turns multiple times

[enric]

We noticed you have downloaded some turns multiple times. If you are having any technical issues please report them to at http://www.slitherine.com/forum.
We'll do our best to resolve any issues and get you up and running ASAP.

I received this, could it be generated because I play agains myself in a hotseat game? as I did not download multiple times a turn.

[IainMcNeil]

No hotstea does nto generate this. This message gets generated if you downloaded your turn and never uploaded it again. E.g. you lost connection or had a crash.

[enric]

This message gets generated if you downloaded your turn and never uploaded it again. E.g. you lost connection or had a crash.

But I did not experiment this in any game…

[gortwillsaveus]

I also received this message last night in an e-mail and did not have a connection failure, or notice anything different about any of the 4-5 games I played last night.
I suppose this brings up the idea that:

a. The person receiving receiving this message might be downloading a second time because things didn't play out as they had expected when playing their turn. i.e. cheating
b. Your opponent did the above described (see a.)
c. There was a legitimate server disconnect when uploading/downloading your turn.

As for me,..while I do try to win,...I'm also okay with losing,..especially when I royally screw up and deserve to lose.
Might point is,..the message is confusing especially when you might play 5-10 games in a 1-2 hour period,..and it can be hard to know which game it's talking about.
Especially when you see no apparent problem in playing or uploading any of those 5-10 games.

[pipfromslitherine]

You'll never get a message based on your opponent behaviour, only yours. So please don't think that the message tells you anything about anyone else's actions.

Cheers

Pip

[enric]

Ok, but as I'm sure I did not download the turn multiple times something is going wrong in the server, and could be a source of conflicts between players.
Now, when I downloaded the new turn just received, I get an alert, in the game itself, saying the same about multiple downloads.

The best of that server system is that you can play with the security that anyone can cheat. Can you give more info about the logs that tell about the multiple downloads?

[pipfromslitherine]

I would bear in mind that the server outages may well have caused some issues. So I wouldn't worry too much about any false positives that are occuring currently.

It can hardly be a source of conflict with players, as only you would see the message .

I will get the server team to check that everything is working as intended, just to be sure.

Cheers

Pip

[hidde]

pip and/or iain
I think you should look at these threads from the FOG forum.
There is clearly some bug in the system.

viewtopic.php?f=91&t=32857

viewtopic.php?f=84&t=32804

[IainMcNeil]

We're looking in to it - if there are issues we'll get them ironed out ASAP!

[enric]

Today I received a more consistent advise (see below), it's clear that something is going wrong on the server:

"Dear enric,

The server tracks all actions taken by all users in the PBEM++ system and we notice that you have consistently downloaded your turns multiple times.
Please contact technical support via www.slitherine.com/forum to resolve the issue or you may find you are unable to continue to use the PBEM++ server system."

[petirouge]

Hi enric,

We already found a bug on the server logs, which was reporting a download attempt more for already finished games.
We fixed it, but it could be you'll receive other notifications like this one in the next days.
Also, if the system finds no irregular activity in the server logs for a while, it will reset its warning level.

By the way, the system won't ban anyone without us checking all the data. Before doing anything likethis, we always contact you directly!

[enric]

Hi enric,

We already found a bug on the server logs, which was reporting a download attempt more for already finished games.
We fixed it, but it could be you'll receive other notifications like this one in the next days.
Also, if the system finds no irregular activity in the server logs for a while, it will reset its warning level.

By the way, the system won't ban anyone without us checking all the data. Before doing anything likethis, we always contact you directly!

I've a question or maybe a suggestion: If every "important" action is sent to the server when it happens, i.e. when a unit is moved, fired, etc, then, if the connection is lost, either because a computer failure, a network problem or any "other" case, when the user reloads the game again, he/she will get the game at the point where the failure happened, i.e no cheating possible.
This system was/is used by SSG in games like Battles in Normandy, Battle for Italy, etc. but they use the own computer (of the current player) to write the log of moves and then it is vulnerable.
Generating a log of events is an usual procedure in profesional databases, and when a hang up happens we can recover data since last saved following the log of every action done until the hang up happened.

[pipfromslitherine]

We are considering having the system save the turn as it goes along, but we are concerned that this could have issues on systems with very slow upload speeds. Uploading only partial data (e.g. just the orders) would be too tricky to try and piece back together once you reconnected. The system wasn't designed to work that way unfortunately - and even then some games would potentially not be able to work that way.

Solving the issue of genuine disconnection during a turn is definitely something we are trying to find a robust solution for.

Cheers

Pip

[enric]

but we are concerned that this could have issues on systems with very slow upload speeds. Uploading only partial data (e.g. just the orders) would be too tricky to try and piece back together once you reconnected.

You may consider the partial buffering in own computer, i.e. with a background procedure which is sending to the server the actions, and deleting them when the server has received, on a hung, you recover from the last update made by this task. Also you may consider a procedure that after loading, look at the buffer, if it exists (some data was not sent) deal with it.
During a turn the user is spending time "thinking" what to do, or just looking around, but the background task is working all time so, even in bad networks the data is usually sent.
I know, Pip, that in the computer world is always easier to say what should be done, that do it.

[pipfromslitherine]

Heh - correct! It's definitely possible for some games, probably including BA. All our uploading etc happens in the background anyway, so it should be fairly simple from that aspect. But other games have huge data sets, and you can also run into the problem that if you have a large data set with a long upload time, when you actually DO want to end your turn, you either need to wait for the 'background' upload to finish, or we need some way to tell the server that we want to cancel the upload etc.

We really want to find a solution that will work in all situations and for all the PBEM++ games.

Thanks for the ideas though - it's all useful stuff.

Cheers

Pip