Inkwell Vibrant Shadows is designed to run on low-end computers without performance drops, so it is a good choice when heavier shaders are too slow. If your frame rate still dips, the problem is usually your general video settings rather than the pack.
Check your frame rate first
1. Load a world with the shader active.
2. Press F3 to open the debug screen and read the FPS number at the top left.
3. Walk around a busy area, such as a village or a dense forest, to see your worst case.
Lighten the load without losing the comic style
The cartoon shading comes from the shader itself, so lowering these vanilla options keeps the look intact:
- Render Distance. Lower this in Options → Video Settings. It usually has the biggest impact.
- Simulation Distance. Reducing this cuts work done on chunks around you.
- Clouds. Set them to Fast or Off.
- Particles. Set them to Decreased or Minimal.
- Entity Shadows. Turn these off.
- Max Framerate. Cap it so your system is not pushed harder than your monitor needs.
If you use Iris, open the pack's settings from the Shader Packs screen to see whether it offers quality options. Lower anything performance-related there too.
After each change, check F3 again. That way you can tell which setting helped most.