Quick Start Guide
Installation & Setup
Get Ollama running on your system in minutes.
# Linux/macOS
curl -fsSL https://ollama.ai/install.sh | sh
# Windows — Download from ollama.ai and run installer
First Model Download
Start with a lightweight, versatile model.
# Terminal
ollama pull llama2:7b
This downloads the 7B parameter Llama 2 model (approx. 3.8GB).
Test Your Setup
Verify everything works correctly.
# Terminal
ollama run llama2:7b "Hello, world!"
Smart Model Management
List Available Models
ollama list
Remove Unused Models
ollama rm model-name:tag
Update Models
ollama pull model-name:tag
Popular Model Recommendations
| Model | Size | Description |
|---|---|---|
| Llama 2 7B | 3.8GB | Great balance of performance and resource usage. Ideal for general tasks and development. |
| Code Llama 7B | 3.8GB | Specialized for code generation, debugging, and programming assistance. |
| Mistral 7B | 4.1GB | High-quality responses with excellent instruction following capabilities. |
| Neural Chat 7B | 4.1GB | Optimized for conversational AI and chat applications. |
Performance Optimization
GPU Acceleration
Ollama automatically detects and uses GPU acceleration when available. Ensure you have CUDA (NVIDIA) or Metal (Apple) support.
# Check GPU usage
nvidia-smi # For NVIDIA
activity monitor # For Apple Silicon
Memory Management
Set memory limits to prevent system overload:
# Set in environment
export OLLAMA_MAX_MEMORY=8GB
Concurrent Requests
Configure parallel request handling:
# Set max concurrent requests
export OLLAMA_MAX_QUEUE=10
Model Loading
Keep frequently used models in memory:
ollama run llama2:7b --keep-alive 30m
WARNING
Resource Requirements: 7B models require at least 8GB RAM, 13B models need 16GB+, and 70B models require 64GB+ RAM for optimal performance.
API Integration Tips
REST API Examples
Basic Chat Completion
# cURL
curl http://localhost:11434/api/generate \
-d '{
"model": "llama2:7b",
"prompt": "Why is the sky blue?",
"stream": false
}'
Python Integration
import requests
import json
response = requests.post('http://localhost:11434/api/generate',
json={
'model': 'llama2:7b',
'prompt': 'Explain quantum computing',
'stream': False
})
result = response.json()
print(result['response'])
Streaming Responses
const response = await fetch('http://localhost:11434/api/generate', {
method: 'POST',
headers: { 'Content-Type': 'application/json' },
body: JSON.stringify({
model: 'llama2:7b',
prompt: 'Write a story about AI',
stream: true
})
});
const reader = response.body.getReader();
while (true) {
const { done, value } = await reader.read();
if (done) break;
const chunk = new TextDecoder().decode(value);
const data = JSON.parse(chunk);
console.log(data.response);
}
Advanced Techniques
Custom Model Files
Create specialized models with custom parameters.
# Modelfile
FROM llama2:7b
PARAMETER temperature 0.8
PARAMETER top_p 0.9
SYSTEM "You are a helpful coding assistant."
# Build Model
ollama create my-coding-assistant -f ./Modelfile
Prompt Engineering
Optimize prompts for better responses.
- Be specific and clear in instructions
- Use examples for complex tasks
- Break down complex requests
- Specify output format when needed
Context Window Management
Efficiently handle long conversations.
# Limit context length
ollama run llama2:7b \
--context-length 2048 \
"Your prompt here"
Parameter Tuning Guide
| Parameter | Range | Default | Effect |
|---|---|---|---|
| temperature | 0.0 - 2.0 | 0.8 | Controls randomness (0=deterministic, 2=very creative) |
| top_p | 0.1 - 1.0 | 0.9 | Nucleus sampling threshold |
| top_k | 1 - 100 | 40 | Limits vocabulary to top K tokens |
| repeat_penalty | 0.0 - 2.0 | 1.1 | Reduces repetition (1.0=no penalty) |
| num_predict | 1 - 2048 | 128 | Maximum tokens to generate |
Troubleshooting Common Issues
Out of Memory Errors
- Use smaller models (7B instead of 13B)
- Reduce context length
- Close other memory-intensive applications
- Set OLLAMA_MAX_MEMORY environment variable
Slow Response Times
- Check GPU utilization
- Use quantized models (Q4, Q5)
- Keep models loaded with --keep-alive
- Reduce num_predict parameter
Connection Issues
- Verify Ollama service is running
- Check port 11434 is accessible
- Restart Ollama service
- Check firewall settings