Benchmark results¶
The latest available Android measurements for each comparison are collected here. Use the performance guide to choose what to try on your screen, and the benchmark runbook to reproduce Haze's workloads. Sections use different devices and builds: compare configurations within a table, not timings across sections.
Reading the results¶
- CPU frame duration measures UI-thread and RenderThread cost, not GPU shader duration.
- Frame overrun measures how far a frame finishes past its deadline. Negative values mean spare time; more negative is better.
- P90 describes the slower end of the measured frames. Negative P90 overrun does not mean every frame met its deadline.
These are measurements of specific sample workloads, not performance budgets for other apps. Each section records its aggregation method and measurement conditions.
Performance modes¶
This comparison measures Adaptive, Quality, Balanced, and Performance with stable
and continuously changing source input. It used a Pixel 8a running Android 17 (full SDK 37.2)
at 60 Hz, with fixed-performance mode enabled and normal Android CPU scheduling.
Values are P90 CPU frame duration / P90 frame overrun, in milliseconds, from one pass with eight iterations per method. Other style choices stay fixed within each sample.
Blur¶
| Workload | Adaptive | Quality | Balanced | Performance |
|---|---|---|---|---|
| Stable source | 5.16 / -7.27 | 4.38 / -7.64 | 5.41 / -7.40 | 3.20 / -8.52 |
| Continuously changing source | 4.66 / -6.15 | 4.72 / -4.98 | 4.49 / -6.07 | 5.03 / -6.28 |
Glass¶
| Workload | Adaptive | Quality | Balanced | Performance |
|---|---|---|---|---|
| Stable source | 3.99 / -10.41 | 3.45 / -10.74 | 3.27 / -10.78 | 3.90 / -10.37 |
| Continuously changing source | 4.21 / -8.76 | 3.51 / -1.68 | 4.90 / -4.98 | 4.59 / -8.62 |
All configurations had spare time at P90. For changing-input Glass, Balanced left about
5 ms of deadline margin, compared with 1.7 ms for Quality. Performance used roughly
9% less median peak GPU memory than Quality.
A single pass is not a mode ranking
Changing-input CPU timings did not produce a consistent ranking. Glass Quality had
the lowest CPU P90 but the least deadline margin; the CPU metric alone cannot explain
GPU cost. This forward-order pass does not control order effects or CPU placement.
Compare appearance and repeat measurements on your screen before choosing an override.
Measurement details
The benchmarkRelease build used commit d1d12494; the Android build was
CP41.260814.003.B1. The device was on AC power at 100% charge and reported thermal
status 0 before and after the matrix. Brightness was unchanged and not recorded.
Glass kept the other GlassDefaults values unchanged.
The 16 methods produced 128 measured iterations and 128 Perfetto traces. Order was Blur stable, Blur changing, Glass stable, then Glass changing; each group ran Adaptive, Quality, Balanced, then Performance.
A combined method selector executed only the first method. Its clean eight-iteration result was retained; all remaining methods were invoked and verified individually. An earlier attempt affected by a stale Google-app Chromium trace producer was stopped and replaced. The Google app was restored after measurement.
Blur rows did not all record GPU memory. Raw JSON, benchmark messages, and traces are
retained locally under
internal/benchmark/build/benchmark-results/performance-levels-latest/.
See ADR-0004 and ADR-0005 for adaptive-policy decisions, and ADR-0006 for the public terminology.
Backdrop versus Sources¶
Native Android Backdrop reads pixels behind the effect from the window, instead of using
captured hazeSource content. See Backdrop guidance for
its practical benefits, fallback requirements, and experimental feature flag.
This comparison used Quality on a Pixel 8a running Android 17 (full SDK 37.2) at 60 Hz,
with fixed-performance mode enabled and normal CPU scheduling. Each method ran eight
iterations in each of two passes, reversing both method and workload order.
Values are the arithmetic mean of the two per-pass P90s, not the P90 of pooled frames.
| Quality workload | Sources CPU P90 (ms) | Backdrop CPU P90 (ms) | Backdrop CPU difference | Sources overrun P90 (ms) | Backdrop overrun P90 (ms) |
|---|---|---|---|---|---|
| Blur, stable input | 4.59 | 5.07 | 10% higher | -7.75 | -2.44 |
| Blur, changing input | 4.59 | 5.12 | 12% higher | -5.40 | -2.21 |
| Glass, stable input | 3.54 | 5.18 | 46% higher | -10.69 | -0.48 |
| Glass, changing input | 3.46 | 4.24 | 23% higher | -1.84 | -0.48 |
| Nine Glass nodes, changing input | 3.94 | 4.74 | 20% higher | -6.85 | -5.18 |
Backdrop had higher CPU P90 in both passes for changing-input Blur and all Glass workloads. All rows retained negative P90 overrun, but Backdrop left less deadline margin. Stable Blur's ranking reversed between passes, so its average does not establish a consistent difference.
Stable input is not an idle screen
These workloads continuously invalidate the effect while leaving source pixels unchanged. They compare retained source output with repeated native Backdrop composition. Use the changing-input rows as the closer reference for scrolling or animated content. These results do not establish that Backdrop is slower on every screen.
Measurement details
The benchmarkRelease build used commit f06cd64a; the Android build was
CP41.260814.003.B1. The device was on AC power at 100% charge. The first pass started
at thermal status 0 and battery temperature 26.0°C; after cooling, the reverse pass
started at thermal status 0 and 28.1°C. Brightness was unchanged and not recorded.
Ten methods, eight iterations each, and two passes produced 160 measured iterations and 160 Perfetto traces. The first pass ran Sources then Backdrop for each workload. One interrupted second-pass attempt was replaced; no completed comparison was discarded. The Google app was force-stopped to prevent its Chromium trace producer from adding a known collection delay. Table values and percentage differences were calculated before rounding.
Native Backdrop trace counters were present with zero source records, confirming that
the native rows did not measure source fallback. Backdrop also used less peak GPU memory:
the recorded difference was approximately 6–10 MB, based on the mean of each pass's
median memoryGpuMaxKb value.
Perfetto showed scheduler variation: the mean per-iteration RenderThread time share on the little CPU cluster ranged from 0.9% to 49.6% across method executions. Stable Glass remained slower with comparable placement in the first pass and more favourable Backdrop placement in the reverse pass. This supports a narrower conclusion: native Backdrop was not a CPU performance win for this Glass scene on this device.
Raw JSON, benchmark messages, and traces are retained locally under
internal/benchmark/build/pixel8a-2026-09-12-full-backdrop-2pass/.
Glass fixed quality¶
This comparison isolates six qualityFraction settings for one 280 dp × 180 dp Regular
Glass surface using HazeInput.Sources. It used a Pixel 6 running Android 17 (full SDK 37.1)
at 60 Hz, with fixed-performance mode enabled.
Controlled CPU placement
The sample's main thread and RenderThread were restricted to the middle CPU cluster. These are controlled quality comparisons, not expected timings under normal Android scheduling. Do not combine them with the Pixel 8a mode results above.
The table shows changing-input results. Each value is the arithmetic mean of two per-pass P90s, calculated before rounding, not the P90 of pooled frames.
qualityFraction |
CPU frame duration: mean per-pass P90 (ms) | Frame overrun: mean per-pass P90 (ms) |
|---|---|---|
0 |
3.17 | -10.95 |
0.25 |
3.12 | -10.17 |
1f / 3f |
3.11 | -9.77 |
0.5 (Balanced) |
3.17 | -9.11 |
0.75 |
4.87 | -6.34 |
1 (Quality) |
4.74 | -5.53 |
For this scene, Fixed(0.75f) left 2.77 ms less deadline margin than Balanced.
No measured frame missed its deadline. These results do not establish the right setting
for Web, Clear Glass, larger or multiple surfaces, or higher refresh rates. Check both
appearance and frame timing on the actual screen under normal scheduling.
Measurement details
The sweep used a release build. The sample process requested affinity to CPUs 4–5; every Perfetto trace confirmed that main and RenderThread executed only on those CPUs during measurement. Other Android processes remained unrestricted.
Six levels ran with stable and changing input, first in ascending quality order, then descending with workload order reversed. Eight iterations per case produced 192 iterations and 34,753 measured frames. No completed timing iteration was discarded. Runs started at thermal status 0 and a battery temperature at most 30°C. Brightness was fixed during measurement; cooldowns dimmed the screen and disabled fixed-performance mode.
The largest changing-input CPU P90 difference between passes was 0.12 ms. Stable-input CPU P90 ranged from 2.60 to 2.72 ms across all levels and both passes.
An earlier normal-scheduling experiment showed CPU rankings sensitive to slower-core placement, including a reversed ranking when two levels were repeated. That experiment remains in git history. This controlled sweep also fixed brightness, so differences between the experiments cannot be attributed to CPU affinity alone.
Representative workloads¶
These Glass sample measurements cover paging, an animated timeline, and steady-state scenes with different effect counts. They used a Pixel 6 running Android 17/API 37 at 60 Hz, with locked CPU frequency and eight iterations per scenario.
| Scenario | Workload | P90 CPU frame duration |
|---|---|---|
productPager |
Gallery paging journey | 7.5 ms |
playgroundTimeline |
Gallery animated timeline journey | 11.2 ms |
steadyFull |
Controlled steady state, 1 Glass effect | 5.6 ms |
steadyFull3 |
Controlled steady state, 3 Glass effects | 5.2 ms |
steadyFull9 |
Controlled steady state, 9 Glass effects | 8.1 ms |
The Gallery journeys are closer to visible user interactions than the steady-state controls. The effect-count rows are separate workload measurements, not a per-effect cost formula: three effects were not slower than one in this run. Measure the content and interactions your application actually uses.
Measurement details
The benchmarkRelease build used commit 334557df. Display resolution was 1080×2400
and render rate was locked to 60 Hz.
Cold-initialization effectAttach* results are omitted because they attach effects at
the measurement boundary and diagnose delegate/shader creation rather than representative
interactions. They remain covered by the benchmark runbook.
For the historical scrolling and dragging comparison between Haze 1 and Haze 2, see the migration guide.