Arm/tinyllama-1-1b-chat-onnx-genai-int4-kquantlast-emb-int8-vivo-x300

TinyLlama-1.1B-Chat-v1.0 optimized for Arm-based mobile CPUs with SME2

A decoder-only chat language model for text generation, provided in ONNX for the ONNX Runtime GenAI runtime and quantized to INT4 groupwise asymmetric weights with INT8 per-token dynamic activations, INT8 per-row embeddings and an INT8 LM head, targeting Arm-based mobile CPUs with SME2.

Summary

This repository contains an Arm-optimized version of TinyLlama/TinyLlama-1.1B-Chat-v1.0 for text generation. The model is provided in ONNX for the ONNX Runtime GenAI runtime, targeting Mobile CPU systems. The transformer weights are quantized with GPTQ to INT4, asymmetric per-group with group size 32, activations are INT8 per-token dynamic, and the embedding table and LM head are INT8.

This version is intended to demonstrate efficient inference on Arm-based platforms while preserving the original model's intended behavior. Arm has evaluated this model on HellaSwag and measured performance on a representative evaluation target.

Key results

Area	Result
Model format	ONNX
Target device class	Mobile CPU
Reference device	vivo X300 (C1-Ultra, C1-Premium, C1-Pro, Android 16 / OriginOS 6)
Primary performance result	34.80 tokens/sec decode throughput (4.27x the FP32 baseline); 726.50 ms time to first token, which is 22.6 % faster than the FP32 baseline
Accuracy result	HellaSwag 59.0 %
Size / memory result	727.86 MB with INT4 weights, INT8 activations, INT8 embeddings and INT8 LM head (5.77x smaller than the FP32 baseline); peak memory 897.54 MB

Original model

Field	Value
Original model	TinyLlama/TinyLlama-1.1B-Chat-v1.0
Original source	Hugging Face
Original developer	The TinyLlama project
Original model card	TinyLlama/TinyLlama-1.1B-Chat-v1.0
Original license	Apache-2.0

Model files

File	Description
model.onnx	Arm-optimized INT4-weight model graph for deployment; weights ship in the model.onnx.data side-car
example.py	Minimal inference example
pyproject.toml	Pinned runtime dependencies for example.py, resolved with uv
uv.lock	Locked dependency resolution for pyproject.toml
config.yaml	Model I/O contract used by the example
benchmarks/	FP32 baseline and Arm-optimized benchmark records

Performance

Performance was measured on the reference configuration below. Results are intended to make the optimization reproducible but do not guarantee identical performance on every Arm-based system.

Reference configuration

Field	Value
Device / platform	vivo X300
CPU / accelerator	C1-Ultra, C1-Premium, C1-Pro, aarch64, CPU execution backend
OS	android, Android 16 / OriginOS 6
Runtime	ONNX Runtime 1.27.0
Backend / delegate	MLAS, KleidiAI
Batch size	1
Precision	INT4 groupwise asymmetric weights (GPTQ, group size 32), INT8 per-token dynamic activations, INT8 per-row embeddings, INT8 LM head (scheme W4A8_dyn_emb_int8)
Runs	5 warmup runs + 20 measured runs

Measurement conditions. Each measured run consumes a 153-token prompt and generates 128 tokens, using 4 CPU threads, 5 warm-up runs and 20 measured runs. Each run starts only once Android reports thermal status 0 (NONE), after a 30 s settle. The device is set to fixed performance mode, which is the official recommendation.

Performance results

Metric	Original / baseline	Arm-optimized	Improvement
End-to-end latency p50 (ms)	16658.09	4394.52	3.79x faster
End-to-end latency p90 (ms)	16835.99	4727.38	3.56x faster
End-to-end latency p99 (ms)	16910.87	4769.23	3.55x faster
Decode throughput (tokens/sec)	8.15	34.80	4.27x
Time to first token (ms)	938.04	726.50	1.29x faster
Model load time (ms)	7604.93	1358.55	5.60x faster
Model size (MB)	4196.99	727.86	5.77x smaller
Peak memory (MB)	4098.56	897.54	4.57x less
Average memory (MB)	4079.43	877.93	4.65x less

Accuracy

Accuracy was evaluated using the same preprocessing, input resolution, and evaluation protocol described below. Where possible, the optimized model is compared against the original model under the same evaluation conditions.

Evaluation setup

Field	Value
Dataset	HellaSwag
Split	validation (0-shot)
Number of samples	8000
Metric(s)	HellaSwag accuracy, acc_norm convention (character-length-normalized)
Evaluation runtime	ONNX Runtime 1.27.0

Accuracy results

Metric	Original / baseline	Arm-optimized	Change
HellaSwag accuracy (%)	59.8	59.0	-0.8 pp

Accuracy was measured using the evaluation setup described above. Users should re-evaluate the model on their own data before production use.

Arm optimization approach

Arm optimized this model for efficient inference on Arm-based platforms using a hardware-aware conversion and validation flow.

For this release, Arm used:

Optimization area	Applied?	Notes
Model conversion	Yes	Converted to ONNX in the ONNX Runtime GenAI graph layout, with attention fused into a single GroupQueryAttention op and the KV cache wired internally
Quantization	Yes	GPTQ weight-only quantization to INT4, asymmetric per-group with group size 32, calibrated on 256 randomly selected WikiText2 samples; INT8 per-token dynamic activations; INT8 per-row embedding table; INT8 LM head protected by k_quant_last (scheme W4A8_dyn_emb_int8)
Runtime/backend selection	Yes	ONNX Runtime 1.27.0 CPU execution provider, with MLAS and KleidiAI kernels
Accuracy validation	Yes	Compared against the original model or published baseline
Performance validation	Yes	Measured on the reference Arm platform

The goal of this process is to improve deployment characteristics such as latency, memory use, model size, and runtime compatibility while preserving the model's intended behavior. Detailed conversion scripts, calibration configuration, or backend-specific implementation details may be provided separately where appropriate.

Using this model

Note: The Python/uv example runs on AWS Graviton (Ubuntu arm64) to confirm runtime compatibility only, and is intended as a guideline for building an equivalent run script on Mobile CPU systems. Every performance and accuracy figure on this page was measured on the vivo X300; none of them was re-measured on the proxy, and a run on the proxy is not evidence about the phone.

Install dependencies

Dependencies are declared in pyproject.toml, which ships with this repository. Resolve and install them into a local virtual environment with uv:

uv python install
uv sync --frozen

Run the example

uv run example.py

The example writes predictions.json next to example.py.

Expected input

Property	Value
Input shape	[1, T], where T is the runtime sequence length, variable up to 2048
Input type	int64, input_ids
Input range	Token ids in the range 0 to 31999, for a vocabulary size of 32000
Preprocessing	Apply the chat template in chat_template.jinja, then tokenize with tokenizer.json with special tokens added. position_ids is not exposed as a graph input, and KV-cache I/O is wired up internally by the ONNX Runtime GenAI Generator.

Expected output

Property	Value
Output shape	One token id per decode step, streamed by the ONNX Runtime GenAI Generator
Output type	Token ids, integer indices into the 32000-entry vocabulary
Postprocessing	Decode with tokenizer.json, stopping on the EOS token or when max_length is reached

Intended use

This model is intended for developers evaluating text generation workloads on Arm-based platforms. It is suitable as a reference implementation for benchmarking, prototyping, and integration exploration.

Limitations

• Performance depends on the target device, runtime version, backend/delegate support, memory configuration, and system load.
• Accuracy was evaluated on HellaSwag and may not generalize to all domains. It does not measure code, math, multi-turn instruction following, or long-context behavior.
• This release preserves the original model's intended task and behavior, but users should validate it for their own application, data, and deployment environment.
• This repository is not a replacement for the original model documentation.

Additional notes

• The ONNX Runtime GenAI bundle requires the literal file names model.onnx and model.onnx.data, because genai_config.json hard-references them.
• The context window is inherited unchanged from the base model at 2048 tokens.
• The quantization recipe is selective: the final LM-head projection is kept at INT8 rather than INT4 (k_quant_last), so some layers were skipped from INT4 quantization to keep accuracy within acceptable ranges.
• Accuracy evaluation scope is HellaSwag zero-shot acc_norm only.

About this version

Original Model: TinyLlama/TinyLlama-1.1B-Chat-v1.0 by The TinyLlama project - Repository

Optimization/conversion: Arm-Optimized version for execution on Arm-based platforms.

Converted/optimized by: Arm

License: The Original Model and the Optimized Model are subject to Apache-2.0.

This repository contains a converted or optimized version of the Original Model (the “Optimized Model”). The Original Model has been converted or optimized as described above for execution on Arm-based platforms.

No retraining or fine-tuning of the Original Model was performed as part of the conversion or optimization. The conversion or optimization was not intended to change the Original Model’s behavior or intended use.

Original Model and Documentation

For information about the Original Model, including its development, training data, intended uses, limitations and other relevant information, please refer to the Original Model repository. Information in that repository was provided by the original developer or other third parties and, unless expressly stated otherwise, has not been independently verified by Arm.

Licenses and Third-Party Terms

Use of the Original Model and the Optimized Model is subject to the applicable licenses, usage restrictions and other terms identified above and in the relevant repositories. Publication of the Optimized Model does not grant any rights beyond those provided under the applicable license terms.

You are responsible for reviewing those terms and ensuring that your use of the Original Model and the Optimized Model is permitted.

Purpose of this Release

The Optimized Model is provided as a reference implementation to demonstrate and evaluate execution and performance on Arm-based systems. It is not a production-ready or supported solution.

Arm’s publication of the Optimized Model does not constitute an endorsement or certification of the Original Model or a representation that the Optimized Model is suitable for production use or any particular purpose.

To the fullest extent permitted by applicable law (i) the Optimized Model is provided “as is.” Arm makes no representations or warranties that the Original Model, the Optimized Model or their outputs are accurate, safe, secure, non-infringing, legally compliant, suitable for production use or fit for any particular purpose; and (ii) Arm will not be liable for any loss or damage arising from or in connection with the Optimized Model, its use or its outputs.

You are responsible for independently evaluating the Optimized Model, its outputs and its suitability for your intended use, including compliance with applicable legal, regulatory, safety and security requirements.

Arm does not commit to provide ongoing support, maintenance or updates for the Optimized Model. Any use of or reliance on the Optimized Model or its outputs is at your own risk.