[0.14.5] Multiplayer autosave experience

[Danner]

Me and a friend are running a multiplayer game lasting several sessions. He's the host, I'm the client.
The map we have been building is about 60 MB large at this point.
Our interacting network connection is about 120kb/s (ADSL upload speeds suck), so starting the game takes about 10 minutes to transfer the map.

The issue I wish to report is down to multiplayer autosaving experience degrading in 0.14.x. In fact, it was far better in 0.13.x.

In 0.13.x it worked like this:
- server initiates an autosave
- game pauses
- both players save, finish saving.
- game resumes


In 0.14.x it works like this:
- server initiates an autosave
- game pauses.
- host starts to save. Client is paused, seeing only a "saving" progress bar. This bar remains empty until the host is done saving. Takes about 10 seconds.
- during the host saving process, the host client is frozen. No indicator of saving visible. (I inform my friend on skype that the game is autosaving, because I got the popup as a client)
- game resumes.... once the host is done saving.

But for the client, the problems just began.
- Client now (finally!) begins saving, takes about 30 seconds to finish. A progress bar shows this progress.
- While client is saving, the game is running. The host can move around.... but cannot interact with items!?!
- Once the client is done saving, the client must catch up to the host, because 30 seconds of server time passed.
- This takes several minutes at which the client can only watch a slightly sped up replay of things happening until up to sync.
- The best resolution for both host and client is to manually pause the game and let the client catch up. Not a great experience.

I could live with that. But ...
- Autosaving while near biters is always 100% fatal to the client, as the server is 30 seconds ahead of the client once autosave is done.
- Meaning biters get 30 seconds of free damage to kill the client player avatar.
- As a client, I have to check the time before clearing out biter nests to avoid that fate. I fail at that. A lot.

This is IMO a serious play experience setback compared to 0.13.x

[Loewchen]

See here as well: viewtopic.php?f=23&t=31617

How long does the autosave sequence take in total?
Please upload the log and the save-file.

[Novort]

I had the same experience (though in a smaller scale) and had to rollback to 0.13 to continue our multiplayer game.

Loewchen, for me it's not about save time. Yes, longer saves makes things much worse, but even with autosave taking a couple of seconds this is still a problem. The player with the slowest (but totally playable) box can't control his character while the game is saving and especially while it is catching up. Things are getting worse when you have a complex base, catchup time increases significantly.

There was an idea to disable client-side autosaves in multiplayer, maybe this is the way to go? These saves are useless anyway, next time the client connects it has to download the whole map from scratch.

PS. Partially solved the problem by upgrade of my box and installing undecorator mod, but still playing 0.13 because of this issue.

[Danner]

See here as well: viewtopic.php?f=23&t=31617

How long does the autosave sequence take in total?
Please upload the log and the save-file.

Thanks for that link. I DO spend a lot of time saving, I feel, but not to the point where it is annoying.
Losing half a minute every autosave is not a big deal to me.

Available RAM is not a concern on my laptop (it's a gaming laptop; Intel i7-4710HQ, 8 GB ram).
I did a profiling during last game (windows task manager) and I was at ~12% CPU used, and ~55% memory used when I was trying to "catch up".
Network was also not the bottleneck. In fact, I failed to find any bottlenecks according to the windows task manager.

Saving takes ~10 seconds on the host, and then ~30 seconds on my client computer.
We are seemingly not allowed to save at the same time.
Spending that amount of time saving isn't really a problem.
Having to spend several minutes "catching up" is a problem (unless pausing, in which case it's usually ~15 seconds) .

The save game is available here, sorry for not offering that upfront.
http://www.pvv.org/~andreasd/_autosave1.zip
Log file from a gaming session with this issue, here:
http://www.pvv.org/~andreasd/factorio-previous.log

Also, it appears the map is now twice the size of last time I checked. 120 MB now. Sorry about the earlier inaccuracy.

--

@Novort: I like the idea of clients not saving. As you say, there isn't much need to do that.

[Klonan]

I think having a setting for 'autosaves only on server' would resolve this issue, and i don't see any large way it would cause problems.

Clients could still save manually, and it would prevent your autosave slots being overwritten from joining multiplayer

However i am also moving this to ideas and suggestions, because it isn't a bug

[ssilk]

Added to viewtopic.php?f=80&t=21367 Game Save File and -Speed Related Suggestions

See also viewtopic.php?f=80&t=32968

[posila]

Added "Autosave olny on server" option to 0.14.14. Default value will be "true".