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Measuring DrawThreadPool Utilization (DrawStats)

Kirikiri Z's drawing runs internally through a parallel thread pool called DrawThreadPool ( TVPBeginThreadTask / TVPExecThreadTask / TVPEndThreadTask ). In a KRKRZ_DRAW_STATS=ON build, its utilization is collected with atomic counters and can be observed in an on-screen overlay and in the log.

The main purpose is finding the cause when the main CPU is saturated while the other cores sit idle. This situation is typical on embedded platforms such as the Switch, and this tool lets you narrow it down just by watching from the outside.

Detailed usage and how to read the output are covered in the guide in src/core:

Build

Toggle it with a CMake option. Default is OFF (no effect on production builds).

cmake --preset x64-windows -DKRKRZ_DRAW_STATS=ON
cmake --build build/x64-windows --config Release

When OFF, the measurement macros expand to nothing and no atomic operations are generated.

Threshold tuning

The SCALE in the threshold check pixelNum >= factor * SCALE of GetAdaptiveThreadNum can be overridden at build time.

# 旧 PC 挙動 (1T 多め) で動かしたい場合
cmake --preset x64-windows -DKRKRZ_THREAD_PIXEL_SCALE=500
  • Default is 100 ( chosen from comparisons on actual Switch hardware )
  • With 500 (the old value), single-thread execution dominates on the Switch and the workers go unused

Display and how to read it

Enabling -memoverlay=1 also shows DrawStats in the upper-right corner of the screen.

If the display scrolls too fast to read (for example on actual hardware), use System.setDrawStatsLog to switch to log output every 500 ms ( in an OFF build or when the MemoryOverlay is hidden, it harmlessly does nothing ).