Volume Shader Benchmark Methodology

Advanced GPU testing methodology using volume shader rendering for comprehensive performance analysis

Our volume shader benchmark methodology represents the cutting edge of GPU performance testing, utilizing sophisticated volume shader rendering and ray marching algorithms to create sustained workloads that accurately reflect real-world graphics processing demands. Unlike traditional burst benchmarks that capture only peak performance, our volume shader burn and measure approach reveals how GPUs perform under extended thermal stress, providing critical insights for gaming, professional rendering, and compute workloads.

Through rigorous testing protocols spanning 10-30 minute durations, our methodology captures the complete performance spectrum: initial GPU capabilities, thermal throttling behavior, frame-time consistency, and sustained performance stability. This comprehensive approach makes our volume shader benchmark the gold standard for accurate GPU performance measurement.

Sustained Load Score (SLS) - Volume Shader Benchmark
avg_fps(late) / avg_fps(early)

The Sustained Load Score (SLS) is the cornerstone metric of our volume shader benchmark methodology, measuring GPU performance retention under sustained volume shader rendering load. By comparing average FPS during the final test segment against initial performance (minutes 15-30 vs 0-2 for 30-minute tests), SLS reveals thermal throttling patterns and sustained performance capabilities critical for real-world gaming and rendering workloads.

In volume shader burn and measure testing, an SLS of 1.0 indicates perfect thermal management with no performance degradation, while scores below 0.85 typically reveal significant thermal throttling. This metric is particularly valuable for volume shader benchmarking as it captures how GPUs handle the continuous parallel processing demands of complex volumetric rendering and ray marching calculations.

Frame Time Percentiles (P95FT / P99FT)
95th and 99th percentile frame times in milliseconds

We measure frame time (the duration to render each frame) and calculate percentiles across 1-second windows. P95FT represents the frame time below which 95% of frames fall, providing insight into consistent frame delivery. Lower values indicate better frame pacing and smoother visual experience.

Stutter Frequency Density (SFD)
Proportion of frames exceeding expected frame time

SFD measures the frequency of frame time spikes by identifying frames that take significantly longer than the median (specifically, frames exceeding 1.8× the rolling 10-second median). This metric captures perceptible stutters that impact user experience, with lower values indicating smoother performance.

Time To First Frame (TTFF)
Initial render latency in milliseconds

TTFF measures the time from clicking "Start" to the first rendered frame, capturing shader compilation time, GPU initialization, and initial setup overhead. This metric is important for understanding cold-start performance.

Timing Backend Priority
  1. WebGPU timestamp queries – Highest precision GPU timing
  2. WebGL EXT_disjoint_timer_query – GPU timing for WebGL
  3. performance.now() + rAF – Fallback CPU timing

Results using fallback timing are marked as degraded and may be less accurate.

Data Quality & Reliability

Each result receives a reliability score (0-5 stars) based on:

  • Test duration meeting minimum thresholds
  • Page visibility ratio (≥85% visible)
  • Timing backend quality (non-fallback preferred)
  • Frame time variance stability
  • Absence of anomalies

Windows where the page was hidden for more than 3 seconds are excluded from analysis to ensure accurate measurements.

Related Articles

Understanding Your Results
Learn how to interpret FPS, frame times, SLS, and other performance metrics from our benchmark tests
How Our Benchmark Works
Technical deep dive into ray marching, Mandelbulb fractals, and our WebGL shader implementation
Best Practices
Optimize your testing environment and preparation for accurate, reproducible results
Thermal Throttling Guide
Detect and solve GPU thermal throttling issues through sustained benchmark testing