#!/bin/bash
# Exp 0 feasibility gate for one config: launch vLLM, record startup facts,
# run the smoke subsets through `vllm bench serve`, run a KL probe, stop.
# Usage: ./exp0.sh V-BF16|V-BF16-FI|V-FP8|V-FP4
set -u
CFG=$1
source ~/kvq-env/bin/activate
MODEL=~/models/Qwen3.8-27B
case $CFG in
  V-BF16)    KV=bfloat16; BE=FLASH_ATTN ;;
  V-BF16-FI) KV=bfloat16; BE=FLASHINFER ;;
  V-FP8)     KV=fp8_e4m3; BE=FLASH_ATTN ;;
  V-FP4)     KV=nvfp4;    BE=FLASHINFER ;;
  *) echo "unknown config $CFG"; exit 2 ;;
esac
OUT=~/bench/exp0/$CFG; mkdir -p $OUT; S=~/bench/data/smoke
LOG=$OUT/server.log

echo "== $CFG: kv=$KV backend=$BE  $(date -u)"
vllm serve $MODEL --served-model-name Qwen/Qwen3.8-27B --port 8000 --dtype bfloat16 \
  --max-model-len 163840 --gpu-memory-utilization 0.90 --reasoning-parser qwen3 --seed 0 \
  --kv-cache-dtype $KV --attention-backend $BE > $LOG 2>&1 &
PID=$!

# Wait up to 30 min for the server (first FlashInfer start JIT-compiles kernels).
for i in $(seq 1 180); do
  if curl -sf localhost:8000/health >/dev/null; then echo "server ready after $((i*10))s"; break; fi
  if ! kill -0 $PID 2>/dev/null; then echo "SERVER_EXITED"; tail -40 $LOG; echo "EXP0_FAIL $CFG"; exit 1; fi
  sleep 10
done
curl -sf localhost:8000/health >/dev/null || { echo "SERVER_TIMEOUT"; tail -40 $LOG; kill $PID; echo "EXP0_FAIL $CFG"; exit 1; }

echo "== startup facts"
grep -iE "kv cache|attention backend|Using .*backend|maximum concurrency|cache_dtype|kv_cache_dtype|nvfp4|fp8" $LOG \
  | grep -v "Gloo\|NCCL" | tail -15 | tee $OUT/startup_facts.txt

BENCH="vllm bench serve --backend openai-chat --endpoint /v1/chat/completions --base-url http://localhost:8000 \
  --model Qwen/Qwen3.8-27B --tokenizer $MODEL --skip-chat-template --disable-shuffle --no-oversample \
  --custom-output-len -1 --save-result --save-detailed --result-dir $OUT --num-warmups 0"

run() {  # name file n concurrency effort temperature [extra args]
  local name=$1 file=$2 n=$3 conc=$4 eff=$5 temp=$6; shift 6
  echo "== bench $name"
  $BENCH --dataset-path $S/$file --num-prompts $n --max-concurrency $conc --temperature $temp \
    --extra-body "{\"reasoning_effort\":\"$eff\"}" --result-filename $name.json "$@" 2>&1 \
    | grep -E "Successful requests|Failed requests|Benchmark duration|Mean TTFT|Output token throughput|Error|Traceback"
}
run ruler_4k    ruler_4k_26.jsonl   26 26 low  0   --dataset-name custom
run ruler_128k  ruler_128k_13.jsonl 13 4  low  0   --dataset-name custom
run docvqa      docvqa_20.jsonl     20 20 low  0   --dataset-name custom_image --custom-ensure-client-side-data --custom-output-len 16384
run gpqa        gpqa_8.jsonl        8  8  xhigh 1.0 --dataset-name custom --top-p 0.95 --top-k 20
run lcb         lcb_10.jsonl        10 10 xhigh 1.0 --dataset-name custom --top-p 0.95 --top-k 20

echo "== KL probe"
python ~/bench/kl_probe.py --out $OUT/kl_probe.json 2>&1 | tail -3

kill $PID; wait $PID 2>/dev/null
echo "EXP0_OK $CFG $(date -u)"