Emulator Issues #13203


Sync GPU with dualcore on netplay causes extreme slowdowns upon looking at EFB effects since 5.0-683/86

Added by crazysheep17 17 days ago.

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Fixed in:


Legend of Zelda Wind Waker

What's the problem? Describe what went wrong.

Upon launching a netplay session with wind waker or any other game with efb effects with both sync gpu and dolphin will slow considerably, down to the same speed as running the game with cached interpreter. This is most evident with wind waker as the into movie shows a sun EFB effect which drops my normally 90fps+ system down to 2-4fps regardless of backend. The game does however then return to full speed after the first loop of the intro, similar slowdowns are experienced in game, but not in menus or anywhere without EFB effects. The game runs at full speed with any of the three settings skip efb EFB access to cpu on (which breaks effects), or dualcore or sync gpu off. This particular combination Only causes slowdowns in Netplay, even with only the host on, and did not exist in 5.0-681 but started in 5.0-686. Prior to this, netplay works with efb effects on, sync gpu and dualcore on with no slowdown. Deterministic dualcore settings have no effect.

Problem exists from 5.0-686 all the way through the current build 5.0-18931. Additionally with this setting combination desyncs are really common and much worse than with sync gpu off, again only since this build and again the problem only exists on netplay even with only the host. Problem replicated on both my wife and is laptop, even in safe mode as i thought it might be some program interfering as it only happens with netplay.

What steps will reproduce the problem?

Make sure EFB copies are on/regular wind waker ini, turn on dual core and sync gpu and launch wind waker in netplay. Wait 5 seconds for the sun to freeze up your system.

Is the issue present in the latest development version? For future reference, please also write down the version number of the latest development version.

yes 5.0-18931

Is the issue present in the latest stable version?

no 5.0

If the issue isn't present in the latest stable version, which is the first broken version? (You can find the first broken version by bisecting. Windows users can use the tool and anyone who is building Dolphin on their own can use git bisect.)


What are your PC specifications? (CPU, GPU, Operating System, more)

Tested on two separate systems, one on windows 11 home one on
Windows 11 pro for workstations insider preview build 25314

32GB 4800 ddr5

intel 12700h

3070ti Laptop higher wattage model

Yes it was tested plugged in with the correct graphics card enabled.

Is there anything else that can help developers narrow down the issue? (e.g. logs, screenshots,
configuration files, savefiles, savestates)

[Anything else here]

No data to display


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