Netplay?

[RachelB]

Quote:except for the small little problem that you save a movie AFTERWARDS

I made this a while ago, might be useful. http://pastie.org/private/sdakiqy4vldwx4syh74g

[tueidj]

(03-06-2014, 11:57 AM)JMC47 Wrote: Netplay makes the emulators sync up very, very well, right down to crashes that I cannot trigger at will.

Except for when it doesn't, which I'm being asked to prove without posting any actual proof i.e. a simple program that shows it doesn't always work.

[RachelB]

(03-06-2014, 05:27 PM)tueidj Wrote:

(03-06-2014, 11:57 AM)JMC47 Wrote: Netplay makes the emulators sync up very, very well, right down to crashes that I cannot trigger at will.

Except for when it doesn't, which I'm being asked to prove without posting any actual proof i.e. a simple program that shows it doesn't always work.

Post a movie of a retail game that desyncs. Or even just tell me you've seen it happen in a movie or netplay. Crafting a program that doesn't work isn't interesting. In all situations that actually matter, it's 100% deterministic.

[LPFaint99]

maybe I read this differently than I should, but I am thinking there is a mis-communication regarding the non reproducible crashes.
If my guess is correct there 'non reproducible crashes' are those such that
there is not series of 'in game steps' that will consistently cause a crash

which is not to say that they won't happen if the input was identical

if a game always crashed at ex Boss battle foo, then it is reproducible with ingame steps
if a game randomly crashes, then they cannot tell you exactly what to do to consistently crash.
I read RachelB's answers as if you have a recording of the input that causes a crash, it will be consistent & reproducible

but without a recording of the inputs, it is almost certainly impossible for you to reproduce exactly the same set of inputs another time

[tueidj]

(03-06-2014, 06:09 PM)RachelB Wrote: Crafting a program that doesn't work isn't interesting. In all situations that actually matter, it's 100% deterministic.

There's nothing a homebrew program can do that a game can't. The percentage of games tested under netplay conditions is miniscule compared to the number of games played under normal mode; there could very well be hundreds of desyncs yet to be discovered. I can't be bothered trying to find one of them when I already have a 100% reproducible example on hand.

As a developer of the program in question, your conduct is terrible - rather than trying to understand the problem and fixing the program, you're more concerned with pretending the problem doesn't exist and refusing to acknowledge anything that proves otherwise.

[delroth]

@tueidj: what example? The time functions are explictly made to be deterministic in netplay/movie mode, and we keep them non deterministic in normal mode because it's way more useful than seeing the internal clock drift compared to the host computer clock.

And yes, of course, NetPlay is not perfect and Dolphin is not perfectly deterministic. But we tend to be pragmatic and prioritize based on 1. what people feel is important to fix; 2. what has a large impact to users. Something that shows up in no games and that doesn't matter to people who develop the emulator will take a while to get fixed, and that's by design. If you think it's so important, feel free to provide patches.

[JMC47]

Honestly, I'd be interested to see some kind of application or something that could desync netplay. As much as I harp about how consistent netplay is; there are times it's desynced and I have no idea why. I have to blame user error because I can't reproduce it; and the next time I try it'll be perfectly stable for 6 - 8 hours until I finally give up and turn off the emulator.

So, yeah, I really don't know. I'd think there'd still be possible cases for desyncs in Dolphin, but I've never been able to find a singular game that could cause it. Maybe Brawl with SD card checked? But even then; there's a VERY, VERY, VERY high chance of user error in that case, and on my testing I was able to get it to sync between my computers, but not to other people who independently setup.

[RachelB]

(03-06-2014, 07:22 PM)tueidj Wrote:

(03-06-2014, 06:09 PM)RachelB Wrote: Crafting a program that doesn't work isn't interesting. In all situations that actually matter, it's 100% deterministic.

There's nothing a homebrew program can do that a game can't. The percentage of games tested under netplay conditions is miniscule compared to the number of games played under normal mode; there could very well be hundreds of desyncs yet to be discovered. I can't be bothered trying to find one of them when I already have a 100% reproducible example on hand.

As a developer of the program in question, your conduct is terrible - rather than trying to understand the problem and fixing the program, you're more concerned with pretending the problem doesn't exist and refusing to acknowledge anything that proves otherwise.

I can't fix a problem that has never once been demonstrated.

Also, i checked and the benchmark is deterministic while a movie is active.

[pauldacheez]

>I tased spider man

WHY

THAT'S NOT NICE

DON'T TASE PEOPLE

[RachelB]

That joke stopped being funny a long time ago :|