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A text-only Qwen test does not establish visual capacity; preserve image preprocessing and measure each multimodal workload separately.
Qwen3-VL memory use depends on the specific model and visual input. A text-only test does not establish the same capacity for images or video. Begin with an exact artifact and a controlled image set, keeping input preparation separate from answer generation.
The result should describe a tested visual profile, not a claim that a GPU can handle every kind of image understanding.
Fix the model and input processor
Qwen3-VL-8B-Instruct is an official example distinct from text-only Qwen3-8B and other VL sizes. Preserve the revision, processor and message template.
vLLM’s multimodal-input documentation describes supported input paths. Verify the combination of runtime version, model and format. Changing image preparation can change the workload even when the original file remains identical.
Build an image matrix
Use authorised examples and define expected answers before testing. Include a simple object, small text and several details in one image if those occur in the intended task.
| Scenario | What to observe |
|---|---|
| One simple image | Baseline preparation and answer |
| Text in an image | Characters and numeric accuracy |
| Several images | Combined resource use |
| Larger visual input | Behaviour within configured limits |
Do not assign universal dimensions from this table. Use supported settings for the chosen implementation and save the actual dimensions, image count, order and question.
Separate stages and resources
File retrieval, decoding and preprocessing can use CPU, RAM and disk before GPU inference begins. Record those stages and the full result time. Host RAM is not added to VRAM as one interchangeable capacity.
Compare the same page at two resolutions and a separate page with different layout. This distinguishes a change in computational size from a change in content difficulty. Also check temporary files and resource release after an unsuccessful or cancelled request.
Evaluate accuracy beside speed
For text, record omissions, invented characters and incorrect numbers. For objects, check whether the answer follows the question and introduces nonexistent details. A lower-memory preparation setting is not automatically an improvement if it loses necessary information.
Increase complexity gradually. Video, if supported by the intended implementation, requires a separate frame-selection and temporal profile; one frame does not describe an entire clip.
The report should include model, processor, visual limits, context and observed memory, with untested data types clearly identified. This provides a concrete basis for discussing a pilot without claiming universal multimodal capacity.
Continue with DeepSeek-OCR GPU Requirements: Test Accuracy and Memory and CUDA Out of Memory on Long Prompts: Check the Context.