Every graphics team knows the feeling: the demo hits 60 fps on the lead engineer’s machine, then collapses into a stuttery mess on real hardware—right when
the marketing capture starts. Now add AI into the pipeline: you’re not just shipping shaders and textures; you’re shipping a model, runtime, drivers, and
“helpful” heuristics that can turn one bad frame into a whole second of visual regret.
The next decade of real-time rendering is not “AI replaces rasterization.” It’s messier and more interesting: each frame becomes a negotiated settlement
between classic rendering and neural inference. Half rendered, half generated. And ops will own the outcome—latency, memory, determinism, regressions, and
weird artifacts that only show up after three hours in a desert biome with fog enabled.
What “half-generated” actually means
When people say “AI graphics,” they usually mean one of three things: (1) upscale a low-res render to high-res, (2) generate intermediate frames between
real frames, or (3) denoise an image produced by a noisy renderer (path tracing, stochastic effects). Those are the mainstream, shipping, “works on a
Tuesday” uses.
But “the frame that’s half-generated” is broader. It’s a pipeline where the engine deliberately renders less than a final image requires, and uses AI to
fill in what was skipped—resolution, samples, geometry detail, shading detail, even parts of the G-buffer. In other words, AI isn’t a post-process. It’s
a co-processor making up for missing compute or missing time.
The important operational distinction: a post-process can be disabled when things go sideways. A co-processor changes what “correct output” means. That
affects testing, debugging, and what you can reasonably roll back under incident pressure.
The mental model that won’t betray you
Treat the hybrid frame as a multi-stage transaction with strict budgets:
- Inputs: depth, motion vectors, exposure, jitter, previous frames, sometimes normals/albedo.
- Classical render: raster, compute, maybe partial ray tracing at reduced samples/res.
- Neural inference: reconstruct or synthesize missing details from inputs plus history.
- Composition: HUD/UI, alpha elements, post FX that must remain crisp and stable.
- Presentation: frame pacing, VRR, frame generation, capture/streaming implications.
If you can’t describe which stage owns which pixels, you can’t debug it. “The model did it” is not a root cause. It’s a confession.
Where AI slots into the pipeline (and where it shouldn’t)
1) Upscaling: buying pixels with math
Upscaling is the gateway drug because it’s easy to justify: render at 67% resolution, spend a couple milliseconds on reconstruction, ship a sharper image
than naive bilinear. The operational problem is that upscalers are temporal. They use history. That means:
- Motion vectors must be correct or you get ghosting and “rubber” edges.
- Exposure/tonemapping must be stable or you get shimmer and breathing.
- Camera cuts, UI overlays, and particles become special cases.
2) Frame generation: buying time with prediction
Frame generation (FG) inserts AI-synthesized frames between “real” frames. This is not the same as doubling performance. You are trading latency and
occasional hallucinations for smoother motion. That’s fine for some games, terrible for others, and complicated for anything competitive.
The core SRE question: what’s your latency SLO? If you can’t answer that, you’re basically rolling dice with user input. Sometimes the dice come up “buttery.”
Sometimes they come up “why did my parry miss?”
3) Denoising: buying samples with priors
Denoising is where neural methods feel inevitable. Path tracing gives you physically plausible lighting but noisy results at low sample counts. Neural
denoisers turn a handful of samples into something presentable by leaning on learned priors. Great—until the priors are wrong for your content.
Denoisers also create a subtle reliability trap: your renderer might be “correct,” but your denoiser is sensitive to input encoding, normal precision,
or subtle differences in roughness ranges. Two shaders that look identical in a classic pipeline can diverge once denoised.
4) The places AI should not own (unless you like firefights)
- UI and text: keep them in native resolution, late in the pipeline. Do not let temporal reconstruction smear your typography.
- Competitive hit feedback: if an AI stage can create or remove a cue, you will get bug reports phrased like legal threats.
- Safety-critical visualization: training sims, medical imaging, anything where a hallucination becomes a liability.
- Deterministic replay systems: if your game relies on replays matching exactly, AI stages must be made deterministic or excluded.
Latency budgets: the only truth that matters
Old rendering arguments were about fps. New arguments are about pacing and end-to-end latency. AI tends to improve average throughput while
worsening tail latency, because inference can have cache effects, driver scheduling quirks, and occasional slow paths (shader compilation, model warmup,
memory paging, power state transitions).
A production pipeline needs budgets that look like SLOs:
- Frame time p50: the normal case.
- Frame time p95: what users remember as “stutter.”
- Frame time p99: what streamers clip and turn into memes.
- Input-to-photon latency: what competitive players feel in their hands.
- VRAM headroom: what prevents intermittent paging and catastrophic spikes.
Frame generation complicates the math because you have two clocks: simulation/render cadence and display cadence. If your sim runs at 60 and you display at 120
with generated frames, your motion looks smoother but your input latency is tied to the sim cadence plus buffering. This is not a moral judgment. It’s physics
plus queues.
A reliable hybrid pipeline does two things aggressively:
- It measures latency explicitly (not just fps).
- It keeps headroom in VRAM, GPU time, and CPU submission so that spikes don’t become outages.
One quote you should keep taped to your monitor, because it applies here more than anywhere: “Hope is not a strategy.” — Gene Kranz.
Joke #1: If your plan is “the model probably won’t spike,” congratulations—you’ve invented probabilistic budgeting, also known as gambling.
Data paths and telemetry: treat frames like transactions
Classic graphics debugging is already hard: a million moving parts, driver black boxes, and timing-sensitive bugs. AI adds a new category of “silent wrong”:
the frame looks plausible, but it’s not faithful. Worse: it’s content-dependent. The bug only shows on a certain map, at a certain time of day, with a
certain particle effect, after the GPU has warmed up.
Production systems survive by observability. Hybrid rendering needs the same discipline. You should log and visualize:
- Per-stage GPU times: base render, inference, post, present.
- Queue depth and backpressure: are frames piling up anywhere?
- VRAM allocations over time: not just “used,” but “fragmented” and “evicted.”
- Inference metrics: model version, precision mode, batch shape, warm/cold state.
- Quality indicators: motion vector validity %, disocclusion rate, reactive mask coverage.
The simplest operational win: stamp every frame with a “pipeline manifest” that records the key toggles and versions that influenced it. If you can’t answer
“what model version produced this artifact?” you don’t have a bug—you have a mystery novel.
Facts and historical context that explain today’s tradeoffs
- 1) Temporal anti-aliasing (TAA) popularized the idea that “the current frame is not enough.” Modern upscalers inherited that worldview.
- 2) Early GPU pipelines were fixed-function; programmability (shaders) turned graphics into software, and software always attracts automation.
- 3) Offline renderers used denoising long before real-time; production film pipelines proved you can trade samples for smarter reconstruction.
- 4) Checkerboard rendering on consoles was a precursor to ML upscaling: render fewer pixels, reconstruct the rest using patterns and history.
- 5) Motion vectors existed for motion blur and TAA before they became critical inputs to AI; now a bad velocity buffer is a quality outage.
- 6) Hardware ray tracing made “noisy but correct” feasible; neural denoisers made “shippable” feasible at real-time budgets.
- 7) The industry learned from texture streaming incidents: VRAM spikes don’t fail gracefully—they fail like a trapdoor under your feet.
- 8) Consoles forced deterministic performance thinking; AI reintroduces variance unless you design for it.
- 9) Video encoders already do motion-compensated prediction; frame generation is conceptually adjacent, but must tolerate interactivity.
New failure modes in hybrid rendering
Artifact taxonomy you should actually use
- Ghosting: history over-trusted; motion vectors wrong or disocclusion not handled.
- Shimmering: temporal instability; exposure, jitter, or reconstruction feedback loop.
- Smearing: inference smoothing detail that should be high-frequency (foliage, thin wires).
- Hallucinated edges: upscaler invents structure; usually from underspecified inputs.
- UI contamination: temporal stage sees UI as scene content and drags it through time.
- Latency “feels off”: frame generation and buffering; sometimes compounded by reflex-like modes misconfigured.
- Random spikes: VRAM paging, model warmup, shader compilation, power state changes, background processes.
The reliability trap: AI hides rendering debt
Hybrid rendering can mask underlying problems: unstable motion vectors, inconsistent depth, missing reactive masks, incorrect alpha handling. The model
covers it… until content shifts and the cover-up fails. Then you’re debugging two systems at once.
If you ship hybrid rendering, you must maintain a “no-AI” fallback path that is tested in CI, not just theoretically possible. This is the difference
between a degraded mode and an outage.
Joke #2: Neural rendering is like a colleague who finishes your sentences—impressive until it starts doing it in meetings with your boss.
Fast diagnosis playbook
When performance or quality goes sideways, don’t start by arguing about “AI vs raster.” Start by finding the bottleneck with a ruthless, staged approach.
The goal is to identify which budget is busted: GPU time, CPU submission, VRAM, or latency/pacing.
First: confirm the symptom is pacing, not average fps
- Check p95/p99 frame time spikes and whether they correlate with scene transitions, camera cuts, or effects.
- Confirm if stutter aligns with VRAM pressure or shader compilation events.
- Validate that the display path (VRR, vsync, limiter) matches test assumptions.
Second: isolate “base render” vs “AI inference” vs “present”
- Disable frame generation first (if enabled). If latency and pacing normalize, you’re in the display/interpolation domain.
- Drop to native resolution (disable upscaling). If artifacts vanish, your inputs (motion vectors, reactive mask) are suspect.
- Switch denoiser to a simpler mode or lower quality. If spikes vanish, inference is the culprit (or its memory behavior).
Third: check VRAM headroom and paging
- If VRAM is within 5–10% of the limit, assume you’ll page under real workloads.
- Look for periodic spikes: these often match streaming, GC-like allocation churn, or background capture.
- Confirm the model weights are resident and not being re-uploaded due to context loss or memory pressure.
Fourth: validate inputs and history integrity
- Motion vectors: correct space, correct scale, correct handling for skinned meshes and particles.
- Depth: stable precision and consistent near/far mapping; avoid “helpful” reversed-Z mismatches across passes.
- History reset on cuts: if you don’t cut history, the model will try to glue two unrelated frames together.
Fifth: regression control
- Pin driver versions for QA baselines. Don’t debug two moving targets at once.
- Pin model versions and precision modes. If you can’t reproduce, you can’t fix.
- Use feature flags with kill-switches that ops can flip without rebuilding.
Practical tasks: commands, outputs, and decisions
These are ops-grade checks you can run on a Linux workstation or build server. They won’t magically debug your shader code, but they will tell you whether
you’re fighting the GPU, the driver stack, memory pressure, or your own process.
Task 1: Identify the GPU and driver in the exact environment
cr0x@server:~$ lspci -nn | grep -Ei 'vga|3d|display'
01:00.0 VGA compatible controller [0300]: NVIDIA Corporation AD104 [GeForce RTX 4070] [10de:2786] (rev a1)
What it means: You’ve confirmed the hardware class. This matters because inference behavior differs by architecture.
Decision: If bug reports mention different device IDs, split the issue by architecture first; don’t average them together.
Task 2: Confirm kernel driver and firmware versions
cr0x@server:~$ uname -r
6.5.0-21-generic
What it means: Kernel updates can change DMA behavior, scheduling, and IOMMU defaults—enough to alter stutter.
Decision: Pin the kernel for performance test baselines. Upgrade intentionally, not accidentally.
Task 3: Confirm NVIDIA driver version (or equivalent stack)
cr0x@server:~$ nvidia-smi
Wed Jan 21 10:14:32 2026
+-----------------------------------------------------------------------------------------+
| NVIDIA-SMI 550.54.14 Driver Version: 550.54.14 CUDA Version: 12.4 |
|-----------------------------------------+------------------------+----------------------|
| GPU Name Persistence-M | Bus-Id Disp.A | Volatile Uncorr. ECC |
| Fan Temp Perf Pwr:Usage/Cap | Memory-Usage | GPU-Util Compute M. |
| | | MIG M. |
|=========================================+========================+======================|
| 0 NVIDIA GeForce RTX 4070 Off | 00000000:01:00.0 On | N/A |
| 30% 54C P2 95W / 200W | 7420MiB / 12282MiB | 78% Default |
+-----------------------------------------+------------------------+----------------------+
What it means: Driver version and VRAM usage are visible. 7.4 GiB used is not alarming; 11.8/12.2 is.
Decision: If VRAM is consistently >90%, treat it as a paging risk and reduce budgets (textures, RT buffers, model size, history buffers).
Task 4: Watch VRAM and utilization over time to catch spikes
cr0x@server:~$ nvidia-smi dmon -s pucm -d 1 -c 5
# gpu pwr gtemp mtemp sm mem enc dec mclk pclk
# Idx W C C % % % % MHz MHz
0 94 55 - 81 63 0 0 9501 2580
0 102 56 - 88 66 0 0 9501 2610
0 73 53 - 52 62 0 0 9501 2145
0 110 57 - 92 70 0 0 9501 2655
0 68 52 - 45 61 0 0 9501 2100
What it means: You can see bursts. If mem% ramps then drops, you may be paging or reallocating aggressively.
Decision: Correlate spikes to engine events (streaming zones, cutscenes). Add pre-warm or cap allocations.
Task 5: Confirm PCIe link width/speed (hidden throttles happen)
cr0x@server:~$ sudo lspci -s 01:00.0 -vv | grep -E 'LnkCap|LnkSta'
LnkCap: Port #0, Speed 16GT/s, Width x16
LnkSta: Speed 16GT/s, Width x16
What it means: You’re not stuck at x4 because someone used the wrong slot or a BIOS setting.
Decision: If link is downgraded, fix hardware/BIOS before you “optimize” your renderer into a pretzel.
Task 6: Check for CPU frequency scaling (frame pacing killer)
cr0x@server:~$ cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor
powersave
What it means: CPU may be slow to ramp, causing render thread submission stutter.
Decision: For perf testing, set to performance and document it, or your results are fiction.
Task 7: Set performance governor during controlled benchmarks
cr0x@server:~$ sudo cpupower frequency-set -g performance
Setting cpu: 0
Setting cpu: 1
Setting cpu: 2
Setting cpu: 3
What it means: CPU will hold higher clocks more consistently.
Decision: If stutters disappear, you have a CPU scheduling/power issue, not an “AI is slow” issue.
Task 8: Check memory pressure and swap activity
cr0x@server:~$ free -h
total used free shared buff/cache available
Mem: 62Gi 41Gi 3.1Gi 1.2Gi 18Gi 19Gi
Swap: 8.0Gi 2.4Gi 5.6Gi
What it means: Swap usage suggests the system is paging. That can manifest as periodic spikes and asset hitching.
Decision: Reduce memory footprint, fix leaks, or increase RAM. Don’t pretend GPU tuning will fix host paging.
Task 9: Identify top CPU consumers (background capture tools are frequent villains)
cr0x@server:~$ ps -eo pid,comm,%cpu,%mem --sort=-%cpu | head
PID COMMAND %CPU %MEM
4121 chrome 38.2 4.1
9332 obs 22.7 1.9
7771 game-bin 18.4 6.8
1260 Xorg 9.2 0.6
2104 pulseaudio 3.1 0.1
What it means: Your “benchmark” is competing with a browser and a streamer tool.
Decision: Reproduce under clean conditions. If OBS is required, treat it as part of the production workload.
Task 10: Check disk I/O latency (asset streaming and model loads)
cr0x@server:~$ iostat -xz 1 3
Linux 6.5.0-21-generic (server) 01/21/2026 _x86_64_ (16 CPU)
avg-cpu: %user %nice %system %iowait %steal %idle
12.41 0.00 3.28 2.91 0.00 81.40
Device r/s rkB/s rrqm/s %rrqm r_await rareq-sz w/s wkB/s wrqm/s %wrqm w_await wareq-sz aqu-sz %util
nvme0n1 92.0 18240.0 0.0 0.00 3.12 198.3 44.0 5280.0 2.0 4.35 5.44 120.0 0.36 18.40
What it means: r_await/w_await are modest. If you see 50–200ms awaits, you’ll get hitches regardless of GPU.
Decision: If storage is slow, fix streaming (prefetch, compression, packaging) before touching inference settings.
Task 11: Validate filesystem space (logs and caches can fill disks mid-run)
cr0x@server:~$ df -h /var
Filesystem Size Used Avail Use% Mounted on
/dev/nvme0n1p2 220G 214G 6.0G 98% /
What it means: You’re one enthusiastic debug logging session away from a bad day.
Decision: Free space or redirect caches/logs. A full disk can break shader caches, model caches, and crash dump writing.
Task 12: Inspect GPU error counters (hardware/driver instability)
cr0x@server:~$ sudo journalctl -k -b | grep -Ei 'nvrm|gpu|amdgpu|i915' | tail
Jan 21 09:58:11 server kernel: NVRM: Xid (PCI:0000:01:00): 31, pid=7771, name=game-bin, Ch 0000002c, intr 00000000
Jan 21 09:58:11 server kernel: NVRM: GPU at PCI:0000:01:00: GPU has fallen off the bus.
What it means: That’s not an optimization problem. That’s a stability incident: driver reset, power issue, or hardware fault.
Decision: Stop tuning quality. Reproduce under stress tests, check power, thermals, and driver known issues.
Task 13: Check GPU clocks and throttling reasons
cr0x@server:~$ nvidia-smi -q -d CLOCK,PERFORMANCE | sed -n '1,80p'
==============NVSMI LOG==============
Performance State : P2
Clocks
Graphics : 2580 MHz
Memory : 9501 MHz
Clocks Throttle Reasons
Idle : Not Active
Applications Clocks Setting : Not Active
SW Power Cap : Not Active
HW Slowdown : Not Active
HW Thermal Slowdown : Not Active
What it means: No obvious throttling. If thermal slowdown is active during spikes, your “AI regression” may be just heat.
Decision: If throttling appears after minutes, test with fixed fan curves and case airflow before rewriting the pipeline.
Task 14: Confirm model files are not being reloaded repeatedly (cache thrash)
cr0x@server:~$ lsof -p $(pgrep -n game-bin) | grep -E '\.onnx|\.plan|\.bin' | head
game-bin 7771 cr0x mem REG 259,2 31248768 1048612 /opt/game/models/upscaler_v7.plan
game-bin 7771 cr0x mem REG 259,2 8421376 1048620 /opt/game/models/denoiser_fp16.bin
What it means: The model weights are memory-mapped. Good. If you see repeated open/close patterns in traces, you’re paying load costs mid-game.
Decision: Preload and pin models at startup or level load; don’t lazily load on first explosion.
Task 15: Check for shader cache behavior (compilation stutter often blamed on AI)
cr0x@server:~$ ls -lh ~/.cache/nv/GLCache | head
total 64M
-rw------- 1 cr0x cr0x 1.2M Jan 21 09:40 0b9f6a8d0b4a2f3c
-rw------- 1 cr0x cr0x 2.8M Jan 21 09:41 1c2d7e91a1e0f4aa
-rw------- 1 cr0x cr0x 512K Jan 21 09:42 3f4a91c2d18e2b0d
What it means: Cache exists and is populated. If it’s empty every run, your environment is wiping it or permissions are wrong.
Decision: Ensure shader caches persist in test and production. Otherwise you’ll chase “random” frame spikes forever.
Task 16: Measure scheduling jitter on the host (useful for render thread pacing)
cr0x@server:~$ sudo cyclictest -m -Sp90 -i200 -h400 -D5s | tail -n 3
T: 0 ( 2345) P:90 I:200 C: 25000 Min: 5 Act: 7 Avg: 9 Max: 112
T: 1 ( 2346) P:90 I:200 C: 25000 Min: 5 Act: 6 Avg: 8 Max: 98
T: 2 ( 2347) P:90 I:200 C: 25000 Min: 5 Act: 6 Avg: 8 Max: 130
What it means: Max jitter in the ~100µs range is usually fine. If you see multi-millisecond jitter, your OS is interrupting you hard.
Decision: For reproducible profiling, isolate CPUs, tame background daemons, and avoid noisy neighbors (VMs, laptop power modes).
Three corporate mini-stories from the trenches
Mini-story #1: The incident caused by a wrong assumption
A studio shipped a patch that “only changed the upscaler.” The release notes said: improved sharpness, fewer artifacts. QA signed off on visual quality in a
controlled scene set, and performance looked stable on their lab machines.
Within hours, support tickets poured in: intermittent hitching, mostly on mid-range GPUs with 8–10 GiB VRAM. The hitches didn’t show up immediately. They
appeared after 20–30 minutes, often after a couple of map transitions. The team blamed shader compilation. It smelled like shader compilation.
The wrong assumption: the new model would be “roughly the same size” in VRAM because it had similar input/output resolution. But the engine’s inference path
quietly enabled a higher-precision intermediate buffer for the new model. Add in a slightly bigger history buffer and a more aggressive reactive mask, and
VRAM headroom vanished.
On those GPUs, the driver started evicting resources. Not always the same ones. The eviction pattern depended on what else was resident: textures, RT
acceleration structures, shadow maps, capture tools. The “shader stutter” was actually memory churn and occasional re-uploads.
The fix wasn’t heroic: cap history resolution, force FP16 intermediates, and reserve VRAM budget explicitly for the model and history buffers. They added a
runtime warning when headroom fell below a threshold and exposed a “safe mode” upscaler that traded sharpness for stability. The lesson was also boring:
treat VRAM as a budget with guardrails, not as a best-effort suggestion.
Mini-story #2: The optimization that backfired
An engine team decided to “save bandwidth” by packing motion vectors and depth into a tighter format. The commit message was cheerful: smaller G-buffer,
faster passes, better cache locality. Benchmarks improved by a couple percent on average. Everyone clapped and moved on.
Then the hybrid pipeline started showing intermittent ghosting on thin geometry—fences, wires, tree branches—especially during fast camera pans. Only some
scenes. Only some lighting. Only some GPUs. The bug reports were vague, because the frames looked “mostly fine” until you stared long enough to hate your
own eyes.
The optimization reduced precision in exactly the places the upscaler relied on: sub-pixel motion and accurate depth discontinuities. The model was trained
assuming a certain distribution of motion errors; the new packing changed the distribution. Not enough to break every frame. Enough to break the hard ones.
The backfire was organizational too. The team had improved one metric (bandwidth) while quietly destroying another (input fidelity). Because input buffers
felt like “internal details,” nobody updated the model validation suite. There was no guardrail for “motion vector quality regression.”
They rolled the packing change back for the AI path while keeping it for the non-AI path. Then they created a contract: motion vector precision and range
became versioned inputs, with automated scene tests that compared temporal stability metrics before and after changes. They still optimized—but only with a
quality budget in the loop.
Mini-story #3: The boring but correct practice that saved the day
A platform team owned the runtime that loaded models, selected precision modes, and negotiated with the graphics backend. Nothing flashy. No one wrote
blog posts about it. But they had one practice that looked like paperwork: every model artifact was treated like a deployable with semantic versioning and a
changelog that included input assumptions.
One Friday, a driver update hit their internal fleet. Suddenly, a subset of machines began showing rare flickers during frame generation—one frame every few
minutes. The flicker was small but obvious in motion. The kind of bug that ruins confidence because it’s rare enough to evade quick reproduction.
Because the model artifacts and runtime were version-pinned and logged per frame, they could answer the crucial question within an hour: nothing in the model
changed. The runtime changed only in a minor way. The driver changed, and only on the affected machines.
They flipped the kill-switch to disable frame generation for that driver branch while leaving upscaling and denoising intact. The game stayed playable. QA
regained a stable baseline. Meanwhile, they worked with the vendor on a minimal repro and verified it against the pinned matrix.
The saving practice wasn’t genius. It was boring operational hygiene: version pinning, per-frame manifests, and fast rollback controls. It turned a potential
weekend incident into a controlled degradation with a clear scope.
Common mistakes: symptoms → root cause → fix
1) Symptom: Ghost trails behind moving characters
Root cause: Motion vectors wrong for skinned meshes, particles, or vertex animation; disocclusion mask missing.
Fix: Validate velocity for each render path; generate motion for particles separately; reset history on invalid vectors; add reactive masks.
2) Symptom: UI text smears or “echoes” during camera movement
Root cause: UI composited before temporal reconstruction, or UI leaks into history buffers.
Fix: Composite UI after upscaling/denoising; ensure UI render targets are excluded from history and motion vector passes.
3) Symptom: Performance is fine in benchmarks, terrible after 30 minutes
Root cause: VRAM fragmentation, asset streaming growth, model weights evicted under pressure, or thermal throttling.
Fix: Track VRAM over time; enforce budgets; pre-warm and pin model allocations; monitor throttling reasons; fix leaks in transient RTs.
4) Symptom: Frame generation feels smooth but input feels laggy
Root cause: Display cadence decoupled from simulation cadence; extra buffering; latency mode misconfigured.
Fix: Measure input-to-photon; reduce render queue depth; tune low-latency modes; offer player-facing toggles with honest descriptions.
5) Symptom: Shimmering on foliage and thin geometry
Root cause: Temporal instability from undersampling plus insufficient reactive mask; precision loss in depth/velocity; aggressive sharpening.
Fix: Improve input precision; tune reactive mask; reduce sharpening; clamp history contribution in high-frequency regions.
6) Symptom: Sudden black frame or corrupted frame once in a while
Root cause: GPU driver reset, TDR-like recovery, out-of-bounds in a compute pass, or model runtime failure path not handled.
Fix: Capture kernel logs; add robust fallback when inference fails; validate bounds and resource states; escalate as stability issue, not “quality.”
7) Symptom: “It only happens on one vendor’s GPU”
Root cause: Different math modes, denormal handling, scheduling, or precision defaults; driver compiler differences.
Fix: Build vendor-specific baselines; constrain precision; test per vendor and per architecture; don’t assume “same API means same behavior.”
8) Symptom: Artifacts appear after camera cut or respawn
Root cause: History not reset; model tries to reconcile unrelated frames.
Fix: Treat cuts as hard resets; fade history contribution; reinitialize exposure and jitter sequences.
Checklists / step-by-step plan
Step-by-step: shipping a half-generated frame without embarrassing yourself
- Define budgets: frame time p95 and p99, VRAM headroom target, input-to-photon target. Write them down. Make them enforceable.
- Version everything: model version, runtime version, driver baseline, feature flags. Log them per frame in debug builds.
- Build a fallback ladder: native render → classic TAAU → ML upscaler → ML + frame gen. Each step must be shippable.
- Validate inputs: motion vectors (all geometry types), depth precision, exposure stability, alpha handling, disocclusion detection.
- Create a temporal test suite: fast pans, foliage, particle storms, camera cuts, respawns, UI overlays. Automate captures and metrics.
- Reserve VRAM: budget history buffers and model weights explicitly; don’t “see what happens.”
- Warm up: precompile shaders, pre-initialize inference, pre-allocate RTs where possible. Hide it behind loading screens.
- Instrument per-stage timings: base render, inference, post, present; include queue depth and pacing metrics.
- Control tail latency: cap worst-case work; avoid allocations in-frame; watch for background CPU contention.
- Ship kill-switches: ops needs toggles to disable FG or swap to a smaller model without a full rebuild.
- Document player tradeoffs: smoothness vs latency, quality modes vs stability. If you hide it, players will discover it the loud way.
- Run endurance tests: 2–4 hours, multiple map transitions, streaming-heavy paths. Most “AI issues” are actually time-based resource issues.
Checklist: before blaming the model
- Is VRAM headroom >10% during worst scenes?
- Are motion vectors valid for every render path (skinned, particles, vertex anim)?
- Do you reset history on cuts and invalid frames?
- Are you compositing UI after temporal stages?
- Are driver and model versions pinned for repro?
- Can you reproduce with AI disabled? If not, your measurement setup is suspect.
FAQ
1) Is “half-generated frame” just marketing for upscaling?
No. Upscaling is one part. “Half-generated” means the pipeline intentionally renders incomplete data and relies on inference to reconstruct or synthesize the rest,
sometimes including time (generated frames) and sometimes including light transport (denoising).
2) Does frame generation increase performance or just hide it?
It increases displayed frame rate, which can improve perceived smoothness. It does not increase simulation rate, and it can increase perceived input latency
depending on buffering and latency modes. Measure input-to-photon, don’t argue in circles.
3) What’s the #1 operational risk when adding AI to rendering?
Tail latency and memory behavior. Average frame time might improve while p99 gets worse due to VRAM eviction, warmup, driver scheduling, or occasional slow paths.
4) Why do artifacts often show up on foliage and thin geometry?
Those features are high-frequency and often under-sampled. They also produce hard disocclusions and unreliable motion vectors. Temporal reconstruction is fragile
when the inputs don’t describe motion cleanly.
5) Can we make AI stages deterministic for replays?
Sometimes. You can constrain precision, fix seeds, avoid non-deterministic kernels, and pin runtimes/drivers. But determinism across vendors and driver versions
is hard. If deterministic replays are a product requirement, design the pipeline with a deterministic mode from day one.
6) Should we ship one big model or multiple smaller ones?
Multiple. You want a ladder: high quality, balanced, safe. Production systems need graceful degradation. One big model is a single point of failure with a
fancy haircut.
7) How do we test “quality” without relying on subjective screenshots?
Use temporal metrics: variance over time, edge stability, ghosting heuristics, disocclusion error counts, and curated “torture scenes.” Also keep human review,
but make it focused and repeatable.
8) What should ops demand from graphics teams before enabling frame generation by default?
A measured latency impact, a kill-switch, clear player messaging, and a regression matrix across driver versions and common hardware. If they can’t provide that,
enabling by default is a reliability gamble.
9) Why does “it works on my machine” get worse with AI?
Because you’ve added more hidden state: model caches, precision modes, driver scheduling differences, VRAM headroom variance, and thermal/power profiles. The
system is more path-dependent, which punishes sloppy baselines.
Conclusion: what to do next week
The frame that’s half-generated is not a science project anymore. It’s a production pipeline with all the usual sins: budgets ignored, versions unpinned,
caches wiped, and “optimizations” that delete the very signals the model needs. The good news is that the fixes look like normal engineering:
measurement, guardrails, and controlled rollouts.
Next week, do these practical things:
- Define p95/p99 frame time and input-to-photon targets, and make them release gates.
- Add per-frame manifests: model/runtime/driver versions and key toggles, logged in debug builds.
- Build a tested fallback ladder and wire it to a kill-switch ops can use.
- Track VRAM headroom and paging risk as a first-class metric, not an afterthought.
- Automate temporal torture scenes and validate motion vectors like your job depends on it—because it does.
Hybrid rendering will keep evolving. Your job is to make it boring in production: predictable, observable, and recoverable when it misbehaves. The “AI” part is
impressive. The “pipeline” part is where you either ship—or spend your weekends watching frame time graphs like they’re stock charts.