DLSS 4.5 UE 5.7.4 MFG crashes with Pacer flush timed out

Gaming and Visualization Technologies DLSS
,
1

Hi,

I’m intergrading DLSS v8.5.0 UE plugin into UE5.7.4, occurred a GPU time out crash when MFG enabled. I had Reflex enabled, FG 2x and auto mode work fine. Here is the crash log:

LogStreamlineAPI: Warning: [15-50-46][streamline][warn][tid:54300[24s:093ms:060us]thread.h:221[flush] Worker thread ‘sl.pacer’ timed out

LogStreamlineAPI: Warning: [15-50-46][streamline][warn][tid:54300][24s:093ms:202us]dlfg.cpp:636[processFrame] Pacer flush has timed out on frame 1012.

LogD3D12RHI: Warning: GPU timeout: A payload (0x000002A55D698350) on the [0x000002A102A53A40, 3D] queue has not completed after 5.000001 seconds.

LogRHI: Warning: Active GPU breadcrumbs:
Device 0, Pipeline Graphics: (In: 0x80d30428, Out: 0x80d303e3)

    (ID: 0x80d301aa) \[     Active\]  Frame 20539

    (ID: 0x80d303e3) \[     Active\]      RenderGraphExecute - 

    (ID: 0x80d30426) \[     Active\]          StreamlineTagTextures

    (ID: 0x800444c6) \[     Active\]			  FlushPendingRHIBarriers

    (ID: 0x80d30428) \[     Active\]              slSetTag

Tried adding TdrDelay and TdrDiDelay into regedit, still crashed. Since dlfg.cpp is close source, it’s hard to do any debug, could you please help to support?

Spec
RTX 5090
Driver
596.21

2

Could you please provide full log file?

3

Hi, here is the full log.
Enabled r.Streamline.LogFunctions and r.Streamline.LogFunctions.LogLevel=2 to print more info in case it helps.

DLSS_MFG_Crash.log (2.2 MB)

Thanks for your reply.

4

I’m having the same issue as well. Have you found any solution on your end?

5

Not yet, I tried upgrading to 8.6.1, same crash occurred for 5x and 6x.
The only clue is if I run with -d3ddebug, there won’t be crash

7

Have you resolved this issue? I’m still struggling with it myself, though the difference is that I encounter GPU timeout (TDR) errors even when using 2x mode. I plan to try reverting to a plugin version that doesn’t include the MFG feature to see if the problem persists.
Judging by the stack trace associated with the TDR, the issue appears to be related to both UE’s GPU Heap GC and the NVIDIA driver.