⚡ Flash Model Benchmarks

This section reports the performance of Flash models on NPU with FastFlowLM (FLM).

Note:

  • Results are based on FastFlowLM v1.0.12 (main build), under FLM’s default NPU power mode (Performance).
  • Newer versions may deliver improved performance.
  • Flash models are single-turn with a fixed 1k-token context, so they are benchmarked with short prompts (64 to 1,024 tokens) rather than the long-context sweeps used for general chat models.
  • Flash only changes how prefill runs. Decode speed matches the non-flash model, so decoding numbers are taken from the corresponding benchmark page.
  • Prompt lengths are the server-reported prompt tokens, chat template included (the 1,024 case is 1,023 tokens). Text-only prompts, no system prompt, median of 7 runs.
  • The 64-token and 128-token cases take about the same time, so prefill TPS at 64 tokens is correspondingly lower.

Test System:

AMD Ryzen™ AI 9 370 (Strix Point) with 32 GB DRAM; performance is comparable to other Strix Point and Strix Halo systems.


🚀 Time to First Token (TTFT, seconds, with different prompt lengths)

Model HW 64 128 256 512 1024
gemma4e-flash:e2b XDNA2 0.20 0.22 0.36 0.73 1.53
gemma4e-flash:e4b XDNA2 0.33 0.34 0.62 1.20 2.57
nemotron3.5-bolt-dflash-flash:e4b XDNA2 0.32 0.33 0.60 1.18 2.53
qwen3vl-flash:4b XDNA2 0.24 0.24 0.45 0.85 1.83
hy-mt2-flash:1.8b XDNA2 0.13 0.14 0.23 0.43 0.84

🚀 Prefill Speed (TPS, or Tokens per Second, with different prompt lengths)

Prompt tokens divided by TTFT (TTFT includes generating the first token).

Model HW 64 128 256 512 1024
gemma4e-flash:e2b XDNA2 322 593 721 705 668
gemma4e-flash:e4b XDNA2 193 373 412 427 398
nemotron3.5-bolt-dflash-flash:e4b XDNA2 201 392 427 434 405
qwen3vl-flash:4b XDNA2 271 526 570 601 558
hy-mt2-flash:1.8b XDNA2 490 923 1,093 1,197 1,214

🚀 Decoding Speed (TPS, or Tokens per Second, starting @ 1k context)

Model HW 1k Source
gemma4e-flash:e2b XDNA2 22.6 Gemma 4 (gemma4-it:e2b)
gemma4e-flash:e4b XDNA2 12.6 Gemma 4 (gemma4-it:e4b)
nemotron3.5-bolt-dflash-flash:e4b XDNA2 18.2 Nemotron Bolt DFlash (nemotron3.5-bolt-dflash:e4b)
qwen3vl-flash:4b XDNA2 19.6 Qwen3 (Qwen 3 4B)
hy-mt2-flash:1.8b XDNA2 52.2 Hy-MT2

Context is fixed at 1k tokens for every flash model, so 1k is the only applicable decode starting point.

nemotron3.5-bolt-dflash-flash:e4b decodes with speculation, so its speed depends on the text: the value above is flm bench (about 30 decoded tokens, mean of 3 runs, 15 to 24 tokens/s between runs). Code and structured answers reach 33 to 40 tokens/s, open prose about 20 (see its model card). The three rows of this model were measured on an AMD Ryzen™ AI MAX+ PRO 395 (Strix Halo) with the same method; on that machine gemma4e-flash:e4b gives 0.32 / 0.32 / 0.58 / 1.17 / 2.52 s.