[AMD] Update v4 args for agentic workload (#38677)

docs/cookbook/autoregressive/DeepSeek/DeepSeek-V4.mdx

@@ -391,10 +391,11 @@ HiCache and MegaMoE are **not** supported on RTX PRO 6000.
 
 - **Model checkpoints** — for correct accuracy, the FP4 model uses the stock `deepseek-ai/DeepSeek-V4-{Flash,Pro}`, and the FP8 model uses the repackaged `sgl-project/DeepSeek-V4-{Flash,Pro}-FP8`.
 - **Supported models** — **MI300X** supports DeepSeek-V4-Flash in FP8; **MI355X** supports DeepSeek-V4-Flash / Pro in both FP4 and FP8. All recipes run single-node.
-- **TP / DP setting (MI355X)** — both TP=4 and TP=8 are supported. At low concurrency we recommend **TP-only**; at high concurrency use **TP + DP** (balanced / high-throughput recipes). The verified MI355X DP recipes additionally set `--dp 8 --enable-dp-attention --enable-dp-attention-local-control-broadcast --enable-two-batch-overlap --tokenizer-worker-num 8 --stream-interval 20 --prefill-decode-interval 10`.
+- **TP / DP setting (MI355X)** — both TP=4 and TP=8 are supported. At low concurrency we recommend **TP-only**; at high concurrency use **TP + DP** (balanced / high-throughput recipes). The verified MI355X DP recipes additionally set `--dp 8 --enable-dp-attention --enable-dp-attention-local-control-broadcast --tokenizer-worker-num 8 --stream-interval 20 --prefill-decode-interval 10`.
 - **MTP** — speculative decoding is supported; add `--speculative-algorithm EAGLE --speculative-num-steps 3 --speculative-eagle-topk 1 --speculative-num-draft-tokens 4`.
 - **Kernels** — uses the Unified KV attention and the flydsl MoE.
 - **FP4 indexer (MI355X)** — FP4 C4 indexer is supported via `--enable-deepseek-v4-fp4-indexer` on top of the standard ROCm recipe.
+- **Agentic long-context (MI355X Pro FP4)** — for multi-turn trace replay, add `--enable-prefill-delayer --prefill-delayer-token-usage-low-watermark 0.7` on the DP path so a single long prefill does not monopolise the engine.
 
 **MoRI EP (AMD expert parallelism)**
 

docs/src/snippets/configs/deepseek-ai/deepseek-v4.jsx

@@ -2875,6 +2875,7 @@ sgl-eval run mmmu_pro \\
         "--model-path {{MODEL_NAME}}",
         "--tp 8",
         "--attention-backend dsv4",
+        "--enable-deepseek-v4-fp4-indexer",
         "--page-size 256",
         "--mem-fraction-static 0.90",
         "--swa-full-tokens-ratio 0.15",
@@ -2913,8 +2914,8 @@ sgl-eval run mmmu_pro \\
         "--tokenizer-worker-num 8",
         "--stream-interval 20",
         "--prefill-decode-interval 10",
-        "--enable-two-batch-overlap",
         "--attention-backend dsv4",
+        "--enable-deepseek-v4-fp4-indexer",
         "--page-size 256",
         "--mem-fraction-static 0.90",
         "--swa-full-tokens-ratio 0.15",
@@ -2953,8 +2954,8 @@ sgl-eval run mmmu_pro \\
         "--tokenizer-worker-num 8",
         "--stream-interval 20",
         "--prefill-decode-interval 10",
-        "--enable-two-batch-overlap",
         "--attention-backend dsv4",
+        "--enable-deepseek-v4-fp4-indexer",
         "--page-size 256",
         "--mem-fraction-static 0.90",
         "--swa-full-tokens-ratio 0.15",