Parameters
2.7B
Context Length
2K
Modality
Text
Architecture
Dense
License
MIT License
Release Date
12 Oct 2023
Knowledge Cutoff
-
VRAM requirements for different quantization methods and context sizes
1,024 tokens
Consumer
1x RTX 4090
24GB VRAM
Datacenter
1x NVIDIA A100
80GB VRAM
Apple Silicon
1x Apple M3 Max
128GB VRAM
2,048 tokens
Consumer
1x RTX 4090
24GB VRAM
Datacenter
1x NVIDIA A100
80GB VRAM
Apple Silicon
1x Apple M3 Max
128GB VRAM
No evaluation benchmarks for Phi-2 available.
Overall Rank
-
Coding Rank
-
Microsoft Phi-2 is a small language model (SLM) with 2.7 billion parameters, representing a continuation of Microsoft Research's efforts in developing highly capable models at a compact scale. The model is designed to facilitate research into language understanding and reasoning while emphasizing efficiency and accessibility. A core objective behind its release is to provide the research community with an unconstrained, small model for investigating crucial safety challenges, including the mitigation of toxicity and the analysis of societal biases within AI systems.
The architectural foundation of Phi-2 is a Transformer-based design, employing a next-word prediction objective. Its training methodology prioritizes data quality, utilizing a substantial corpus of 1.4 trillion tokens derived from both synthetic and meticulously filtered web data. The synthetic component, generated using advanced models like GPT-3.5 and GPT-4, focuses on "textbook-quality" content to impart robust common sense reasoning, general knowledge, and specific domain understanding in areas such as science. Web data underwent stringent filtering to ensure high educational value and content integrity. The training process for Phi-2 spanned 14 days, leveraging a cluster of 96 A100 GPUs, and incorporated techniques such as Flash Attention. Notably, Phi-2 is a base model that has not undergone alignment through reinforcement learning from human feedback (RLHF) or explicit instruction fine-tuning, yet it exhibits favorable behavior regarding toxicity and bias.
Phi-2's performance characteristics position it as a proficient tool for various natural language processing applications, including question answering, conversational AI, and code generation. Its compact parameter count makes it suitable for deployment on consumer-grade GPUs, enabling efficient inference. The model demonstrates strong reasoning and language understanding capabilities, often performing comparably to or surpassing significantly larger models in specific benchmarks. Its design fosters exploration in areas such as mechanistic interpretability and fine-tuning experiments, making it a valuable resource for researchers and developers aiming to innovate with resource-efficient language models.
Attention
Attention Structure
Multi-Head Attention
Attention Heads
32
Key-Value Heads
32
Attention Head Dimension
-
Position Embedding
ROPE
RoPE Theta
10,000
Sliding Window Attention
No
Sliding Window Size
-
Sliding Window Ratio
-
Linear Attention
-
Linear Attention Ratio
-
Normalization
Layer Normalization
Activation Function
GELU
Dimensions
Hidden Dimension Size
2,048
Number of Layers
32
FFN Intermediate Size (Dense)
10,240
Multi-Token Prediction Heads
-
Tokenizer
Vocabulary Size
51,200
Microsoft's Phi-2 is a 2.7 billion parameter Transformer-based model, developed for efficient language understanding and reasoning. Its technical innovations include training on "textbook-quality" synthetic and filtered web data, alongside scaled knowledge transfer from its predecessor, Phi-1.5, facilitating emergent capabilities within a compact architecture.
APX AI
Online