blip2

Guide to BLIP-2 pipeline

1. ViT and Qformer

• Generate ONNX model files for ViT and Qformer

  python onnx_export.py

  The exported ONNX files lies in ./onnx/visual_encoder and ./onnx/Qformer. Moreover, it will save test image tensor to image.pt and visual query tokens to query_tokens.pt for later pipeline inference.

• Build TensorRT engines

  python build_vit_qformer.py 0 # For ViT, FP16
  python build_vit_qformer.py 1 # For Qformer, FP16

  The built engines lie in ./plan/visual_encoder and ./plan/Qformer.

2. BLIP2 OPT-2.7B

• Download OPT-2.7B model checkpoint (same as original OPT-2.7B)

  # OPT-2.7B
  cd ../opt
  git-lfs clone https://huggingface.co/facebook/opt-2.7b

• Convert original checkpoint to TRT-LLM checkpoint format (same as original OPT-2.7B)

  # OPT-2.7B
  python3 convert_checkpoint.py --model_dir ./opt-2.7b \
              --dtype float16 \
              --output_dir ./opt/2.7B/trt_ckpt/fp16/1-gpu/

• Build TRT-LLM engines from TRT-LLM checkpoint (only need to add --max_prompt_embedding_table_size)

  NOTE: max_prompt_embedding_table_size = query_token_num * max_batch_size, so if you changes the max_batch_size, prompt table size must be reset accordingly.

  # OPT-2.7B
  trtllm-build --checkpoint_dir=./opt/2.7B/trt_ckpt/fp16/1-gpu/ \
                  --max_batch_size 8 \
                  --use_gpt_attention_plugin float16 \
                  --use_gemm_plugin float16 \
                  --max_input_len 924 \
                  --max_output_len 100 \
                  --max_beam_width 5 \
                  --output_dir ../blip2/trt_engine/blip-2-opt-2.7b/fp16/1-gpu \
                  --max_prompt_embedding_table_size 256 # 256 = 32 (query_token number) * 8 (max_batch_size)

  The built OPT engines lie in ./trt_engine/blip-2-opt-2.7b/fp16/1-gpu.

  UPDATE[2023-09-21]: We have newly added INT8/INT4 weight-only support for OPT. So you can enable it using commands as follows (take INT4 as an example, while INT8 is the default precision for weight-only quantization):

  # OPT-2.7B
  python3 convert_checkpoint.py --model_dir ./opt-2.7b \
              --dtype float16 \
              --output_dir ./opt/2.7B/trt_ckpt/int4_weightonly/1-gpu/
              --use_weight_only \
              --weight_only_precision int4
  
  trtllm-build --checkpoint_dir=./opt/2.7B/trt_ckpt/int4_weightonly/1-gpu/ \
                  --max_batch_size 8 \
                  --use_gpt_attention_plugin float16 \
                  --use_gemm_plugin float16 \
                  --max_input_len 924 \
                  --max_output_len 100 \
                  --max_beam_width 5 \
                  --output_dir ../blip2/trt_engine/blip-2-opt-2.7b/int4_weightonly/1-gpu \
                  --max_prompt_embedding_table_size 256 # 256 = 32 (query_token number) * 8 (max_batch_size)

  The built OPT engines lie in ./trt_engine/blip-2-opt-2.7b/int4_weightonly/1-gpu.

3. Assemble everything into BLIP-2 pipeline FP16 pipeline

   # BLIP OPT-2.7B
   cd ../blip2
   python run.py --num_beams 1 \
                 --max_txt_len 32 \
                 --max_output_len 30 \
                 --input_text "Question: which city is this? Answer:" \
                 --engine_dir ./plan \
                 --opt_engine_dir trt_engine/blip-2-opt-2.7b/fp16/1-gpu \
                 --input_dir image.pt \
                 --query_tokens query_tokens.pt

   INT8/INT4 weight-only quantization pipeline

   # BLIP OPT-2.7B
   cd ../blip2
   python run.py --num_beams 1 \
                 --max_txt_len 32 \
                 --max_output_len 30 \
                 --input_text "Question: which city is this? Answer:" \
                 --engine_dir ./plan \
                 --opt_engine_dir trt_engine/blip-2-opt-2.7b/int4_weightonly/1-gpu \
                 --input_dir image.pt \
                 --query_tokens query_tokens.pt