Add 12 AI infrastructure and LLM operations skills

New skills covering hot-topic AI engineering subjects:

Local AI Infrastructure:
- vllm-server: High-throughput LLM serving with PagedAttention, tensor parallelism, quantization
- llm-inference-scaling: KEDA-based GPU autoscaling for LLM inference on Kubernetes
- rag-infrastructure: Production RAG with hybrid search, reranking, and embedding pipelines
- llm-fine-tuning: QLoRA/LoRA fine-tuning with Axolotl, DeepSpeed ZeRO-3, and DPO alignment

Infrastructure:
- gpu-server-management: NVIDIA driver setup, MIG partitioning, DCGM monitoring
- vector-database-ops: Qdrant, Weaviate, pgvector for production AI search
- llm-gateway: LiteLLM-based API gateway with rate limiting, virtual keys, fallback routing

DevOps/AI:
- llm-cost-optimization: Model right-sizing, prompt/semantic caching, batch API, break-even analysis
- llm-caching: Multi-layer exact + semantic + provider caching to cut costs 30-70%
- ai-pipeline-orchestration: Prefect/Airflow/Dagster for RAG ingestion and training workflows

Orchestration:
- model-serving-kubernetes: KServe + Triton with canary deployments and GPU autoscaling

Security:
- ai-security-hardening: Prompt injection defense, PII scrubbing, model weight verification

https://claude.ai/code/session_011MN1C4PrkCeg2Qmi7q1ZUe
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---
name: vector-database-ops
description: Deploy, manage, and optimize vector databases for AI applications. Covers Qdrant, Weaviate, pgvector, and Pinecone — collection management, indexing strategies, backup, and performance tuning for production RAG and semantic search workloads.
license: MIT
metadata:
author: devops-skills
version: "1.0"
---
# Vector Database Operations
Run production vector databases for AI-powered search, RAG, and recommendation systems.
## When to Use This Skill
Use this skill when:
- Setting up a vector database for a RAG or semantic search application
- Choosing between Qdrant, Weaviate, pgvector, or Pinecone
- Managing collections, indexes, and data migrations
- Optimizing query performance and indexing for production loads
- Implementing multi-tenant vector search with namespace isolation
## Vector Database Comparison
| Database | Best For | Hosting | Filtering | Scale |
|----------|----------|---------|-----------|-------|
| **Qdrant** | High-performance, rich filtering, self-hosted | Self / Cloud | Excellent | Very High |
| **Weaviate** | Schema-first, hybrid search, multi-modal | Self / Cloud | Good | High |
| **pgvector** | Already on Postgres, simple use cases | Self | Good | Medium |
| **Pinecone** | Zero-ops managed, serverless | Managed only | Good | Very High |
| **Chroma** | Local dev, prototyping | Self only | Basic | Low-Medium |
## Qdrant — Production Deployment
```bash
# Docker (single node)
docker run -d \
--name qdrant \
-p 6333:6333 \
-p 6334:6334 \
-v $(pwd)/qdrant-data:/qdrant/storage \
qdrant/qdrant:latest
# With custom config
docker run -d \
--name qdrant \
-p 6333:6333 \
-v $(pwd)/qdrant-data:/qdrant/storage \
-v $(pwd)/qdrant-config.yaml:/qdrant/config/production.yaml \
qdrant/qdrant:latest
```
```yaml
# qdrant-config.yaml
storage:
storage_path: /qdrant/storage
on_disk_payload: true # store payload on disk (saves RAM)
service:
max_request_size_mb: 32
hnsw_index:
m: 16 # graph connections per node
ef_construct: 100 # accuracy vs build time trade-off
full_scan_threshold: 10000 # switch to brute force below this
quantization:
scalar:
type: int8
quantile: 0.99
always_ram: true # keep quantized index in RAM
telemetry_disabled: true
```
## Qdrant Collection Management
```python
from qdrant_client import QdrantClient
from qdrant_client.models import (
Distance, VectorParams, HnswConfigDiff,
ScalarQuantizationConfig, ScalarType, QuantizationConfig
)
client = QdrantClient("http://localhost:6333")
# Create optimized collection
client.create_collection(
collection_name="documents",
vectors_config=VectorParams(
size=1536, # OpenAI ada-002 / text-embedding-3-small
distance=Distance.COSINE,
on_disk=True, # save RAM — vectors stored on disk
),
hnsw_config=HnswConfigDiff(
m=32, # higher = better recall, more RAM
ef_construct=200,
on_disk=False, # keep HNSW graph in RAM for speed
),
quantization_config=QuantizationConfig(
scalar=ScalarQuantizationConfig(
type=ScalarType.INT8,
quantile=0.99,
always_ram=True,
)
),
)
# Create payload index for fast filtering
client.create_payload_index(
collection_name="documents",
field_name="tenant_id",
field_schema="keyword",
)
client.create_payload_index(
collection_name="documents",
field_name="created_at",
field_schema="datetime",
)
# Collection info
info = client.get_collection("documents")
print(f"Vectors: {info.vectors_count}, Status: {info.status}")
```
## Qdrant Filtered Search
```python
from qdrant_client.models import Filter, FieldCondition, MatchValue, Range
# Tenant-isolated search (multi-tenant RAG)
results = client.query_points(
collection_name="documents",
query=query_embedding,
query_filter=Filter(
must=[
FieldCondition(key="tenant_id", match=MatchValue(value="acme-corp")),
FieldCondition(key="doc_type", match=MatchValue(value="contract")),
],
should=[
FieldCondition(key="created_at", range=Range(gte="2024-01-01")),
],
),
limit=10,
with_payload=True,
)
```
## pgvector — PostgreSQL Extension
```sql
-- Enable extension
CREATE EXTENSION IF NOT EXISTS vector;
-- Create table with vector column
CREATE TABLE documents (
id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
content TEXT NOT NULL,
embedding VECTOR(1536),
metadata JSONB DEFAULT '{}',
tenant_id TEXT NOT NULL,
created_at TIMESTAMPTZ DEFAULT NOW()
);
-- Create HNSW index (faster queries, more memory)
CREATE INDEX ON documents
USING hnsw (embedding vector_cosine_ops)
WITH (m = 16, ef_construction = 64);
-- Create IVFFlat index (less memory, slower build)
-- CREATE INDEX ON documents
-- USING ivfflat (embedding vector_cosine_ops)
-- WITH (lists = 100);
-- Semantic search with metadata filtering
SELECT id, content, metadata,
1 - (embedding <=> $1::vector) AS similarity
FROM documents
WHERE tenant_id = 'acme-corp'
AND metadata->>'doc_type' = 'contract'
ORDER BY embedding <=> $1::vector
LIMIT 10;
```
```bash
# Deploy pgvector via Docker
docker run -d \
--name pgvector \
-e POSTGRES_PASSWORD=secret \
-e POSTGRES_DB=vectordb \
-p 5432:5432 \
-v pgvector-data:/var/lib/postgresql/data \
pgvector/pgvector:pg16
```
## Weaviate Deployment
```yaml
# docker-compose for Weaviate
services:
weaviate:
image: semitechnologies/weaviate:latest
ports:
- "8080:8080"
- "50051:50051"
environment:
QUERY_DEFAULTS_LIMIT: 25
AUTHENTICATION_ANONYMOUS_ACCESS_ENABLED: "false"
AUTHENTICATION_APIKEY_ENABLED: "true"
AUTHENTICATION_APIKEY_ALLOWED_KEYS: "${WEAVIATE_API_KEY}"
AUTHENTICATION_APIKEY_USERS: "admin"
PERSISTENCE_DATA_PATH: /var/lib/weaviate
ENABLE_MODULES: text2vec-openai,generative-openai
OPENAI_APIKEY: "${OPENAI_API_KEY}"
CLUSTER_HOSTNAME: node1
volumes:
- weaviate-data:/var/lib/weaviate
restart: unless-stopped
volumes:
weaviate-data:
```
## Backup and Restore
```bash
# Qdrant — snapshot backup
curl -X POST "http://localhost:6333/collections/documents/snapshots"
# Download snapshot
curl -O "http://localhost:6333/collections/documents/snapshots/documents-snapshot.snapshot"
# Restore
curl -X POST "http://localhost:6333/collections/documents/snapshots/recover" \
-H "Content-Type: application/json" \
-d '{"location": "/qdrant/snapshots/documents-snapshot.snapshot"}'
# pgvector — standard pg_dump
pg_dump -h localhost -U postgres -d vectordb \
--table=documents --format=custom > documents-backup.dump
# Restore
pg_restore -h localhost -U postgres -d vectordb documents-backup.dump
```
## Performance Tuning
```python
# Qdrant — optimize collection after bulk load
client.update_collection(
collection_name="documents",
optimizer_config={"indexing_threshold": 0}, # force indexing now
)
# Wait for optimization to complete
import time
while True:
info = client.get_collection("documents")
if info.status.value == "green":
break
time.sleep(5)
print(f"Optimizing... segments: {info.segments_count}")
```
## Common Issues
| Issue | Cause | Fix |
|-------|-------|-----|
| Slow queries | No HNSW index built yet | Wait for indexing; check `status == green` |
| High RAM usage | Vectors in memory | Enable `on_disk=True` for vectors |
| Poor recall | Low `ef` search param | Increase `ef` in search request (at query time) |
| pgvector slow | Using IVFFlat without vacuum | Run `VACUUM ANALYZE documents` |
| Weaviate OOM | Too many objects | Enable async indexing; increase heap |
## Best Practices
- Use cosine distance for normalized embeddings; dot product for unnormalized.
- Always create payload indexes on filter fields (`tenant_id`, `doc_type`).
- For datasets >10M vectors, use `on_disk` vectors + `always_ram` quantization.
- Benchmark with your actual query patterns before choosing IVFFlat vs HNSW.
- Snapshot before any bulk delete or migration operation.
## Related Skills
- [rag-infrastructure](../../local-ai/rag-infrastructure/) - Full RAG pipeline
- [databases](../databases/) - General database management
- [postgresql](../postgresql/) - pgvector host database ops
@@ -0,0 +1,312 @@
---
name: llm-fine-tuning
description: Set up infrastructure for fine-tuning LLMs with QLoRA, LoRA, and full fine-tuning using Hugging Face TRL, Axolotl, and distributed training with DeepSpeed or FSDP. Covers dataset prep, training runs, and model export.
license: MIT
metadata:
author: devops-skills
version: "1.0"
---
# LLM Fine-Tuning Infrastructure
Train and fine-tune open-source LLMs efficiently — from LoRA on a single GPU to distributed full fine-tuning across multi-node clusters.
## When to Use This Skill
Use this skill when:
- Fine-tuning an LLM on domain-specific data (legal, medical, code, support)
- Running QLoRA to fine-tune 70B models on consumer GPUs
- Setting up distributed training with DeepSpeed or FSDP
- Exporting fine-tuned adapters for production serving
- Implementing RLHF, DPO, or instruction tuning pipelines
## Prerequisites
- NVIDIA GPU(s) with 24GB+ VRAM (RTX 4090 / A100 / H100)
- CUDA 12.1+ and `nvidia-smi` working
- Python 3.10+ with `pip`
- Hugging Face account and `HF_TOKEN` for gated models
- 500GB+ disk for model weights and training data
## Quick Start: QLoRA Fine-Tuning
```bash
pip install transformers datasets trl peft bitsandbytes accelerate
python - <<'EOF'
from datasets import load_dataset
from transformers import AutoTokenizer, AutoModelForCausalLM, BitsAndBytesConfig
from peft import LoraConfig, get_peft_model
from trl import SFTTrainer, SFTConfig
import torch
model_id = "meta-llama/Llama-3.1-8B-Instruct"
# 4-bit quantization (QLoRA)
bnb_config = BitsAndBytesConfig(
load_in_4bit=True,
bnb_4bit_quant_type="nf4",
bnb_4bit_compute_dtype=torch.bfloat16,
bnb_4bit_use_double_quant=True,
)
model = AutoModelForCausalLM.from_pretrained(
model_id, quantization_config=bnb_config, device_map="auto"
)
tokenizer = AutoTokenizer.from_pretrained(model_id)
# LoRA configuration
peft_config = LoraConfig(
r=16, # rank
lora_alpha=32,
target_modules=["q_proj", "k_proj", "v_proj", "o_proj",
"gate_proj", "up_proj", "down_proj"],
lora_dropout=0.05,
bias="none",
task_type="CAUSAL_LM",
)
dataset = load_dataset("your-org/your-dataset", split="train")
trainer = SFTTrainer(
model=model,
args=SFTConfig(
output_dir="./output",
num_train_epochs=3,
per_device_train_batch_size=2,
gradient_accumulation_steps=8,
learning_rate=2e-4,
bf16=True,
logging_steps=10,
save_strategy="epoch",
report_to="wandb",
),
train_dataset=dataset,
peft_config=peft_config,
processing_class=tokenizer,
)
trainer.train()
trainer.save_model("./fine-tuned-model")
EOF
```
## Axolotl (Production Fine-Tuning Framework)
```yaml
# config.yaml — Axolotl QLoRA config for Llama 3.1
base_model: meta-llama/Llama-3.1-8B-Instruct
model_type: LlamaForCausalLM
tokenizer_type: PreTrainedTokenizerFast
load_in_4bit: true
adapter: qlora
lora_r: 32
lora_alpha: 64
lora_dropout: 0.05
lora_target_modules:
- q_proj
- k_proj
- v_proj
- o_proj
- gate_proj
- up_proj
- down_proj
datasets:
- path: your-org/your-dataset
type: alpaca # or sharegpt, chat_template, etc.
dataset_prepared_path: ./prepared-data
val_set_size: 0.05
output_dir: ./output
sequence_len: 4096
sample_packing: true # pack multiple short samples for efficiency
micro_batch_size: 2
gradient_accumulation_steps: 8
num_epochs: 3
learning_rate: 2e-4
optimizer: adamw_bnb_8bit
lr_scheduler: cosine
warmup_ratio: 0.05
bf16: true
flash_attention: true
logging_steps: 10
eval_steps: 100
save_steps: 200
wandb_project: my-fine-tune
```
```bash
# Run with Axolotl
pip install axolotl[flash-attn,deepspeed]
accelerate launch -m axolotl.cli.train config.yaml
```
## Distributed Training with DeepSpeed
```json
// deepspeed_zero3.json — ZeRO Stage 3 (split optimizer + gradients + params)
{
"zero_optimization": {
"stage": 3,
"offload_optimizer": {"device": "cpu", "pin_memory": true},
"offload_param": {"device": "cpu", "pin_memory": true},
"overlap_comm": true,
"contiguous_gradients": true,
"sub_group_size": 1e9,
"reduce_bucket_size": "auto",
"stage3_prefetch_bucket_size": "auto",
"stage3_param_persistence_threshold": "auto",
"stage3_max_live_parameters": 1e9,
"stage3_max_reuse_distance": 1e9,
"gather_16bit_weights_on_model_save": true
},
"bf16": {"enabled": true},
"gradient_clipping": 1.0,
"train_batch_size": "auto",
"train_micro_batch_size_per_gpu": "auto"
}
```
```bash
# Launch 4-GPU DeepSpeed training
deepspeed --num_gpus=4 train.py \
--deepspeed deepspeed_zero3.json \
--model_name meta-llama/Llama-3.1-70B-Instruct \
--output_dir ./output
```
## DPO / RLHF Alignment
```python
from trl import DPOTrainer, DPOConfig
from datasets import load_dataset
# Dataset format: {"prompt": ..., "chosen": ..., "rejected": ...}
dataset = load_dataset("your-org/preference-data")
trainer = DPOTrainer(
model=model,
ref_model=None, # None = implicit reference with peft
args=DPOConfig(
output_dir="./dpo-output",
beta=0.1, # KL divergence weight
num_train_epochs=1,
per_device_train_batch_size=1,
gradient_accumulation_steps=16,
learning_rate=5e-7,
bf16=True,
),
train_dataset=dataset["train"],
peft_config=peft_config,
processing_class=tokenizer,
)
trainer.train()
```
## Merging LoRA Adapters for Deployment
```python
from peft import PeftModel
from transformers import AutoModelForCausalLM
# Load base model in full precision
base_model = AutoModelForCausalLM.from_pretrained(
"meta-llama/Llama-3.1-8B-Instruct",
torch_dtype=torch.bfloat16,
device_map="cpu",
)
# Load and merge LoRA adapter
model = PeftModel.from_pretrained(base_model, "./fine-tuned-model")
merged_model = model.merge_and_unload()
# Save merged model (ready for vLLM serving)
merged_model.save_pretrained("./merged-model", safe_serialization=True)
tokenizer.save_pretrained("./merged-model")
# Push to Hugging Face Hub
merged_model.push_to_hub("your-org/your-fine-tuned-model")
```
## Kubernetes Training Job
```yaml
apiVersion: batch/v1
kind: Job
metadata:
name: llm-fine-tune
spec:
template:
spec:
restartPolicy: OnFailure
nodeSelector:
nvidia.com/gpu.product: A100-SXM4-80GB
containers:
- name: trainer
image: nvcr.io/nvidia/pytorch:24.05-py3
command: ["accelerate", "launch", "-m", "axolotl.cli.train", "/config/config.yaml"]
resources:
limits:
nvidia.com/gpu: "4"
memory: "320Gi"
requests:
nvidia.com/gpu: "4"
volumeMounts:
- name: config
mountPath: /config
- name: model-cache
mountPath: /root/.cache/huggingface
- name: output
mountPath: /output
env:
- name: HUGGING_FACE_HUB_TOKEN
valueFrom:
secretKeyRef:
name: hf-token
key: token
- name: WANDB_API_KEY
valueFrom:
secretKeyRef:
name: wandb-token
key: key
volumes:
- name: config
configMap:
name: axolotl-config
- name: model-cache
persistentVolumeClaim:
claimName: model-cache-pvc
- name: output
persistentVolumeClaim:
claimName: training-output-pvc
```
## Common Issues
| Issue | Cause | Fix |
|-------|-------|-----|
| `CUDA out of memory` | Batch too large | Reduce `micro_batch_size`; increase `gradient_accumulation_steps` |
| Training loss NaN | Learning rate too high | Lower LR to `1e-4` or `5e-5`; add warmup |
| Slow training | No Flash Attention | Install `flash-attn`; enable `flash_attention: true` |
| Poor fine-tune quality | Bad data formatting | Validate dataset format; check `sample_packing` compatibility |
| Adapter merge errors | Mixed quantization | Merge in bf16 on CPU, not in 4-bit |
## Best Practices
- Use Flash Attention 2 — it's 24× faster and uses less memory.
- Monitor training loss/eval loss via W&B or MLflow; overfit = more dropout or less data.
- Validate with a held-out eval set (510%); MMLU or custom evals for quality gates.
- Start with LoRA r=16 before increasing — higher rank = more parameters, diminishing returns.
- Use `sample_packing` in Axolotl to maximize GPU utilization on short sequences.
## Related Skills
- [vllm-server](../vllm-server/) - Serve fine-tuned models
- [gpu-server-management](../../servers/gpu-server-management/) - GPU setup
- [llm-inference-scaling](../llm-inference-scaling/) - Deploy at scale
- [ai-pipeline-orchestration](../../../devops/ai/ai-pipeline-orchestration/) - Training pipelines
@@ -0,0 +1,270 @@
---
name: llm-inference-scaling
description: Auto-scale LLM inference clusters on Kubernetes using KEDA, custom GPU metrics, and horizontal pod autoscaling. Handle traffic spikes, implement queue-based scaling, and optimize cost with spot instances for AI workloads.
license: MIT
metadata:
author: devops-skills
version: "1.0"
---
# LLM Inference Scaling
Scale LLM inference horizontally on Kubernetes with GPU-aware autoscaling, request queuing, and cost-efficient spot instance strategies.
## When to Use This Skill
Use this skill when:
- LLM API traffic is unpredictable and you need to scale up/down automatically
- Managing a fleet of vLLM or TGI inference pods on Kubernetes
- Reducing inference costs with spot/preemptible GPU instances
- Implementing queue-based autoscaling for batch inference jobs
- Building a multi-model serving platform that shares GPU resources
## Prerequisites
- Kubernetes cluster with GPU nodes (NVIDIA operator installed)
- KEDA (Kubernetes Event-Driven Autoscaler) installed
- Prometheus with GPU metrics (`dcgm-exporter` or `gpu-operator`)
- Helm 3+ for chart deployments
## GPU Node Setup
```bash
# Install NVIDIA GPU Operator (handles drivers, container toolkit, DCGM)
helm repo add nvidia https://helm.ngc.nvidia.com/nvidia
helm repo update
helm install gpu-operator nvidia/gpu-operator \
--namespace gpu-operator \
--create-namespace \
--set driver.enabled=true \
--set dcgm.enabled=true \
--set devicePlugin.enabled=true
# Verify GPU nodes are recognized
kubectl get nodes -l nvidia.com/gpu.present=true
kubectl describe node <gpu-node> | grep nvidia
```
## vLLM Deployment with GPU Resources
```yaml
apiVersion: apps/v1
kind: Deployment
metadata:
name: vllm-llama-8b
labels:
app: vllm
model: llama-3.1-8b
spec:
replicas: 1
selector:
matchLabels:
app: vllm
model: llama-3.1-8b
template:
metadata:
labels:
app: vllm
model: llama-3.1-8b
spec:
nodeSelector:
nvidia.com/gpu.present: "true"
tolerations:
- key: nvidia.com/gpu
operator: Exists
effect: NoSchedule
containers:
- name: vllm
image: vllm/vllm-openai:latest
args:
- "--model"
- "meta-llama/Llama-3.1-8B-Instruct"
- "--tensor-parallel-size"
- "1"
- "--gpu-memory-utilization"
- "0.90"
- "--max-num-seqs"
- "128"
resources:
requests:
nvidia.com/gpu: "1"
memory: "20Gi"
cpu: "4"
limits:
nvidia.com/gpu: "1"
memory: "24Gi"
cpu: "8"
ports:
- containerPort: 8000
readinessProbe:
httpGet:
path: /health
port: 8000
initialDelaySeconds: 60
periodSeconds: 10
env:
- name: HUGGING_FACE_HUB_TOKEN
valueFrom:
secretKeyRef:
name: hf-token
key: token
```
## KEDA Autoscaling on Prometheus Metrics
```yaml
apiVersion: keda.sh/v1alpha1
kind: ScaledObject
metadata:
name: vllm-scaledobject
spec:
scaleTargetRef:
name: vllm-llama-8b
minReplicaCount: 1
maxReplicaCount: 8
cooldownPeriod: 300 # 5 min before scale-down
pollingInterval: 15
triggers:
- type: prometheus
metadata:
serverAddress: http://prometheus-server.monitoring:9090
metricName: vllm_num_requests_waiting
threshold: "10" # scale up if >10 requests waiting
query: |
sum(vllm:num_requests_waiting{deployment="vllm-llama-8b"})
- type: prometheus
metadata:
serverAddress: http://prometheus-server.monitoring:9090
metricName: vllm_gpu_cache_usage
threshold: "0.8" # scale up if KV cache >80% full
query: |
avg(vllm:gpu_cache_usage_perc{deployment="vllm-llama-8b"})
```
## Queue-Based Scaling (Redis + KEDA)
```yaml
# ScaledJob for async batch inference
apiVersion: keda.sh/v1alpha1
kind: ScaledJob
metadata:
name: llm-batch-inference
spec:
jobTargetRef:
template:
spec:
containers:
- name: inference-worker
image: myapp/inference-worker:latest
env:
- name: REDIS_URL
value: redis://redis:6379
- name: QUEUE_NAME
value: inference-jobs
restartPolicy: OnFailure
minReplicaCount: 0
maxReplicaCount: 20
pollingInterval: 5
successfulJobsHistoryLimit: 3
triggers:
- type: redis
metadata:
address: redis:6379
listName: inference-jobs
listLength: "5" # 1 worker per 5 queued jobs
```
## Spot Instance Strategy
```yaml
# Mixed node pool: on-demand + spot GPUs
apiVersion: v1
kind: ConfigMap
metadata:
name: cluster-autoscaler-priority-config
data:
priorities: |
10: # low priority = prefer
- .*spot.*
50:
- .*on-demand.*
---
# Node affinity for spot with on-demand fallback
spec:
affinity:
nodeAffinity:
preferredDuringSchedulingIgnoredDuringExecution:
- weight: 80
preference:
matchExpressions:
- key: node.kubernetes.io/lifecycle
operator: In
values: [spot]
- weight: 20
preference:
matchExpressions:
- key: node.kubernetes.io/lifecycle
operator: In
values: [on-demand]
```
## Cluster Autoscaler for GPU Nodes
```bash
# AWS EKS — enable cluster autoscaler for GPU node group
helm install cluster-autoscaler autoscaler/cluster-autoscaler \
--namespace kube-system \
--set autoDiscovery.clusterName=my-cluster \
--set awsRegion=us-east-1 \
--set rbac.serviceAccount.annotations."eks\.amazonaws\.com/role-arn"=arn:aws:iam::ACCOUNT:role/ClusterAutoscalerRole \
--set extraArgs.skip-nodes-with-local-storage=false \
--set extraArgs.expander=least-waste
# Annotate GPU node group for autoscaler
kubectl annotate node <node> \
cluster-autoscaler.kubernetes.io/safe-to-evict="false"
```
## Scaling Metrics to Monitor
```bash
# Prometheus queries for scaling decisions
# Requests waiting in vLLM queue
sum(vllm:num_requests_waiting) by (model)
# GPU KV cache utilization (>80% = bottleneck)
avg(vllm:gpu_cache_usage_perc) by (pod)
# Tokens per second throughput
sum(rate(vllm:generation_tokens_total[5m])) by (model)
# P99 time-to-first-token
histogram_quantile(0.99, rate(vllm:time_to_first_token_seconds_bucket[5m]))
```
## Common Issues
| Issue | Cause | Fix |
|-------|-------|-----|
| Pods stuck in `Pending` | No GPU nodes available | Check cluster autoscaler logs; verify node group limits |
| Scale-up too slow | Cluster autoscaler delay + model load time | Pre-warm replicas; increase `minReplicaCount` |
| GPU fragmentation | Multiple small models on large GPUs | Use MIG partitioning or consolidate model sizes |
| Spot eviction causes errors | Spot instance reclamation | Add `PodDisruptionBudget`; use graceful shutdown |
| KEDA not scaling | Prometheus query returns no data | Test query in Prometheus UI first |
## Best Practices
- Set `minReplicaCount: 1` to avoid cold starts; scale to 0 only for batch jobs.
- Use `PodDisruptionBudget` with `minAvailable: 1` to survive spot evictions.
- Pre-pull model weights into a shared PVC to speed up pod startup by 510×.
- Separate model families across node pools (A10G for 7B, A100 for 70B).
- Use Kubernetes VPA for CPU/memory right-sizing alongside KEDA for replica count.
## Related Skills
- [vllm-server](../vllm-server/) - vLLM configuration and tuning
- [gpu-server-management](../../servers/gpu-server-management/) - GPU node setup
- [model-serving-kubernetes](../../../devops/orchestration/model-serving-kubernetes/) - KServe
- [kubernetes-ops](../../../devops/orchestration/kubernetes-ops/) - Core Kubernetes
- [llm-cost-optimization](../../../devops/ai/llm-cost-optimization/) - Cost strategies
@@ -0,0 +1,253 @@
---
name: rag-infrastructure
description: Build and operate Retrieval-Augmented Generation (RAG) infrastructure with vector stores, embedding pipelines, and hybrid search. Covers ingestion, chunking strategies, reranking, and production deployment patterns.
license: MIT
metadata:
author: devops-skills
version: "1.0"
---
# RAG Infrastructure
Production infrastructure for Retrieval-Augmented Generation: ingest documents, generate embeddings, store in vector databases, and serve grounded LLM responses.
## When to Use This Skill
Use this skill when:
- Building a knowledge base Q&A system over internal documents
- Implementing semantic search over large document collections
- Reducing LLM hallucinations with retrieved context
- Setting up embedding pipelines and vector store infrastructure
- Deploying hybrid search (dense + sparse/BM25)
## Prerequisites
- Python 3.10+ with `pip`
- A vector database (Qdrant, Weaviate, Pinecone, or pgvector)
- An embedding model (OpenAI, Cohere, or local via `sentence-transformers`)
- An LLM endpoint (OpenAI API or self-hosted vLLM)
- Docker for local vector DB deployment
## Architecture Overview
```
Documents → Chunker → Embedder → Vector Store
User Query → Embedder → Vector Store (search) → Reranker → LLM → Answer
```
## Embedding Pipeline
```python
from sentence_transformers import SentenceTransformer
from qdrant_client import QdrantClient
from qdrant_client.models import Distance, VectorParams, PointStruct
import uuid
# Local embedding model (no API cost)
model = SentenceTransformer("BAAI/bge-large-en-v1.5")
# Connect to Qdrant
client = QdrantClient("http://localhost:6333")
# Create collection
client.create_collection(
collection_name="knowledge-base",
vectors_config=VectorParams(size=1024, distance=Distance.COSINE),
)
def ingest_documents(docs: list[dict]):
"""Chunk, embed, and upsert documents."""
points = []
for doc in docs:
chunks = chunk_text(doc["text"], chunk_size=512, overlap=50)
embeddings = model.encode(chunks, batch_size=32, show_progress_bar=True)
for chunk, embedding in zip(chunks, embeddings):
points.append(PointStruct(
id=str(uuid.uuid4()),
vector=embedding.tolist(),
payload={"text": chunk, "source": doc["source"], "title": doc["title"]},
))
client.upsert(collection_name="knowledge-base", points=points)
print(f"Ingested {len(points)} chunks")
```
## Chunking Strategies
```python
from langchain.text_splitter import RecursiveCharacterTextSplitter
def chunk_text(text: str, chunk_size: int = 512, overlap: int = 50) -> list[str]:
"""Recursive character splitter — best general-purpose strategy."""
splitter = RecursiveCharacterTextSplitter(
chunk_size=chunk_size,
chunk_overlap=overlap,
separators=["\n\n", "\n", ". ", " ", ""],
)
return splitter.split_text(text)
# For code/markdown — use language-aware splitter
from langchain.text_splitter import MarkdownHeaderTextSplitter
headers = [("#", "H1"), ("##", "H2"), ("###", "H3")]
md_splitter = MarkdownHeaderTextSplitter(headers_to_split_on=headers)
```
## Hybrid Search (Dense + Sparse)
```python
from qdrant_client.models import SparseVector, SparseVectorParams, NamedSparseVector
from fastembed import SparseTextEmbedding
# Qdrant hybrid collection (dense + BM25 sparse)
client.create_collection(
collection_name="hybrid-kb",
vectors_config={"dense": VectorParams(size=1024, distance=Distance.COSINE)},
sparse_vectors_config={"sparse": SparseVectorParams()},
)
sparse_model = SparseTextEmbedding("prithivida/Splade_PP_en_v1")
def hybrid_search(query: str, top_k: int = 10) -> list[dict]:
dense_vec = model.encode(query).tolist()
sparse_vec = list(sparse_model.embed(query))[0]
results = client.query_points(
collection_name="hybrid-kb",
prefetch=[
{"query": dense_vec, "using": "dense", "limit": 20},
{"query": SparseVector(indices=sparse_vec.indices.tolist(),
values=sparse_vec.values.tolist()),
"using": "sparse", "limit": 20},
],
query={"fusion": "rrf"}, # Reciprocal Rank Fusion
limit=top_k,
)
return [{"text": p.payload["text"], "score": p.score} for p in results.points]
```
## Reranking
```python
import cohere
co = cohere.Client("your-api-key")
def rerank(query: str, candidates: list[str], top_n: int = 5) -> list[str]:
"""Rerank retrieved chunks for relevance (improves RAG quality ~20-30%)."""
response = co.rerank(
model="rerank-english-v3.0",
query=query,
documents=candidates,
top_n=top_n,
)
return [candidates[r.index] for r in response.results]
# Alternative: local reranker (no API cost)
from sentence_transformers import CrossEncoder
reranker = CrossEncoder("cross-encoder/ms-marco-MiniLM-L-6-v2")
def local_rerank(query: str, candidates: list[str], top_n: int = 5) -> list[str]:
pairs = [[query, c] for c in candidates]
scores = reranker.predict(pairs)
ranked = sorted(zip(candidates, scores), key=lambda x: x[1], reverse=True)
return [text for text, _ in ranked[:top_n]]
```
## RAG Query Pipeline
```python
from openai import OpenAI
llm = OpenAI(base_url="http://localhost:8000/v1", api_key="your-key")
def rag_query(user_question: str) -> str:
# 1. Retrieve
candidates = hybrid_search(user_question, top_k=20)
texts = [c["text"] for c in candidates]
# 2. Rerank
top_chunks = local_rerank(user_question, texts, top_n=5)
# 3. Generate
context = "\n\n---\n\n".join(top_chunks)
response = llm.chat.completions.create(
model="meta-llama/Llama-3.1-8B-Instruct",
messages=[
{"role": "system", "content": (
"Answer the question using only the provided context. "
"If the answer isn't in the context, say so.\n\nContext:\n" + context
)},
{"role": "user", "content": user_question},
],
temperature=0.1,
max_tokens=1024,
)
return response.choices[0].message.content
```
## Docker Compose: Full RAG Stack
```yaml
services:
qdrant:
image: qdrant/qdrant:latest
volumes:
- qdrant-data:/qdrant/storage
ports:
- "6333:6333"
restart: unless-stopped
redis:
image: redis:7-alpine
volumes:
- redis-data:/data
restart: unless-stopped
ingestion-worker:
build: ./ingestion
environment:
- QDRANT_URL=http://qdrant:6333
- REDIS_URL=redis://redis:6379
depends_on: [qdrant, redis]
restart: unless-stopped
rag-api:
build: ./api
ports:
- "8080:8080"
environment:
- QDRANT_URL=http://qdrant:6333
- LLM_BASE_URL=http://vllm:8000/v1
depends_on: [qdrant]
restart: unless-stopped
volumes:
qdrant-data:
redis-data:
```
## Common Issues
| Issue | Cause | Fix |
|-------|-------|-----|
| Poor retrieval quality | Chunk size too large | Try 256512 tokens; overlap 1015% |
| LLM ignores retrieved context | Context too long | Rerank and keep top 35 chunks |
| Slow ingestion | Sequential embedding | Use `batch_size=64` and async upserts |
| Stale documents | No re-ingestion pipeline | Track `doc_hash`; re-embed on change |
| High embedding costs | All chunks re-embedded | Cache embeddings with hash-based dedup |
## Best Practices
- Use `BAAI/bge-large-en-v1.5` or `nomic-embed-text` for strong free embeddings.
- Always rerank before passing to LLM — 5 precise chunks beat 20 noisy ones.
- Store source metadata (URL, page, section) in vector payloads for citations.
- Use namespace/tenant isolation in the vector store for multi-tenant RAG.
- Evaluate with RAGAS metrics: faithfulness, answer relevancy, context precision.
## Related Skills
- [vector-database-ops](../../databases/vector-database-ops/) - Qdrant/Weaviate management
- [vllm-server](../vllm-server/) - Self-hosted LLM endpoint
- [ollama-stack](../ollama-stack/) - Local LLM for development
- [ai-pipeline-orchestration](../../../devops/ai/ai-pipeline-orchestration/) - Ingestion pipelines
@@ -0,0 +1,219 @@
---
name: vllm-server
description: Deploy and manage vLLM for high-throughput LLM inference. Configure continuous batching, tensor parallelism, quantization, and OpenAI-compatible API endpoints for production LLM serving.
license: MIT
metadata:
author: devops-skills
version: "1.0"
---
# vLLM Server Management
Deploy production-grade LLM inference servers with vLLM — the fastest open-source LLM serving engine with PagedAttention and continuous batching.
## When to Use This Skill
Use this skill when:
- Serving open-source LLMs (Llama, Mistral, Qwen, Gemma) at scale
- Building an OpenAI-compatible API endpoint for self-hosted models
- Optimizing LLM throughput and latency for production traffic
- Running multi-GPU inference with tensor or pipeline parallelism
- Deploying quantized models to reduce GPU memory requirements
## Prerequisites
- NVIDIA GPU(s) with CUDA 12.1+ (A100/H100 recommended for production)
- Docker or Python 3.9+ with pip
- 40GB+ VRAM for 70B models; 8GB+ for 7B models
- `nvidia-container-toolkit` for Docker GPU passthrough
## Quick Start
```bash
# Install vLLM
pip install vllm
# Serve a model (OpenAI-compatible API)
vllm serve meta-llama/Llama-3.1-8B-Instruct \
--host 0.0.0.0 \
--port 8000 \
--api-key your-secret-key
# Test the endpoint
curl http://localhost:8000/v1/chat/completions \
-H "Content-Type: application/json" \
-H "Authorization: Bearer your-secret-key" \
-d '{
"model": "meta-llama/Llama-3.1-8B-Instruct",
"messages": [{"role": "user", "content": "Hello!"}]
}'
```
## Docker Deployment
```bash
docker run --runtime nvidia --gpus all \
-v ~/.cache/huggingface:/root/.cache/huggingface \
-p 8000:8000 \
--ipc=host \
vllm/vllm-openai:latest \
--model meta-llama/Llama-3.1-8B-Instruct \
--api-key your-secret-key
```
## Docker Compose (Production)
```yaml
services:
vllm:
image: vllm/vllm-openai:latest
runtime: nvidia
environment:
- NVIDIA_VISIBLE_DEVICES=all
- HUGGING_FACE_HUB_TOKEN=${HF_TOKEN}
volumes:
- model-cache:/root/.cache/huggingface
ports:
- "8000:8000"
ipc: host
command: >
--model meta-llama/Llama-3.1-70B-Instruct
--tensor-parallel-size 2
--max-model-len 32768
--gpu-memory-utilization 0.90
--api-key ${VLLM_API_KEY}
restart: unless-stopped
healthcheck:
test: ["CMD", "curl", "-f", "http://localhost:8000/health"]
interval: 30s
timeout: 10s
retries: 3
volumes:
model-cache:
```
## Key Configuration Options
### Multi-GPU Tensor Parallelism
```bash
# Split one model across 4 GPUs
vllm serve meta-llama/Llama-3.1-70B-Instruct \
--tensor-parallel-size 4 \
--gpu-memory-utilization 0.90
```
### Quantization (Lower VRAM)
```bash
# AWQ quantization (70B on 2x A100 40GB)
vllm serve casperhansen/llama-3-70b-instruct-awq \
--quantization awq \
--tensor-parallel-size 2
# GPTQ quantization
vllm serve TheBloke/Llama-2-70B-Chat-GPTQ \
--quantization gptq
# FP8 (H100 NVL native)
vllm serve meta-llama/Llama-3.1-405B-Instruct \
--quantization fp8 \
--tensor-parallel-size 8
```
### Structured Output & Tools
```bash
vllm serve meta-llama/Llama-3.1-8B-Instruct \
--enable-auto-tool-choice \
--tool-call-parser llama3_json \
--guided-decoding-backend outlines
```
### LoRA Adapters
```bash
vllm serve meta-llama/Llama-3.1-8B-Instruct \
--enable-lora \
--lora-modules sql-lora=/path/to/sql-lora \
code-lora=/path/to/code-lora \
--max-lora-rank 64
```
## Performance Tuning
```bash
# Maximize throughput for batch workloads
vllm serve <model> \
--max-num-seqs 256 \ # max concurrent sequences
--max-num-batched-tokens 8192 \ # tokens per batch
--gpu-memory-utilization 0.95 \ # use 95% VRAM
--swap-space 4 # CPU swap (GiB)
# Minimize latency for interactive use
vllm serve <model> \
--max-num-seqs 32 \
--enforce-eager # disable CUDA graph capture
```
## Benchmarking
```bash
# Install benchmark tool
pip install vllm
# Run throughput benchmark
python -m vllm.entrypoints.openai.run_batch \
--model meta-llama/Llama-3.1-8B-Instruct \
--input-file prompts.jsonl \
--output-file results.jsonl
# Benchmark with vllm bench
vllm bench throughput \
--model meta-llama/Llama-3.1-8B-Instruct \
--num-prompts 1000 \
--input-len 512 \
--output-len 128
```
## Monitoring
```bash
# Check running server stats
curl http://localhost:8000/metrics # Prometheus metrics
# Key metrics to watch:
# vllm:num_requests_running - active requests
# vllm:gpu_cache_usage_perc - KV cache utilization
# vllm:generation_tokens_per_s - throughput
# vllm:time_to_first_token_ms - TTFT latency
# vllm:e2e_request_latency_seconds - end-to-end latency
```
## Common Issues
| Issue | Cause | Fix |
|-------|-------|-----|
| `CUDA out of memory` | Model too large for VRAM | Add `--quantization awq` or reduce `--gpu-memory-utilization` |
| Slow cold start | Model not cached | Pre-pull with `huggingface-cli download <model>` |
| Low throughput | Too few concurrent requests | Increase `--max-num-seqs` |
| KV cache full errors | Context length too long | Set `--max-model-len` lower |
| `tokenizer error` | Tokenizer mismatch | Use `--tokenizer` to specify correct tokenizer |
## Best Practices
- Use `--gpu-memory-utilization 0.90` to leave headroom for CUDA kernels.
- Pin model versions with `--revision` for reproducible deployments.
- Set `HF_HUB_OFFLINE=1` in production to prevent unexpected downloads.
- Use AWQ or GPTQ quantization before tensor parallelism — lower VRAM first.
- Enable `--enable-chunked-prefill` for long-context workloads.
- Monitor `gpu_cache_usage_perc` — above 95% causes queuing.
## Related Skills
- [llm-inference-scaling](../llm-inference-scaling/) - Auto-scaling vLLM deployments
- [gpu-server-management](../../servers/gpu-server-management/) - GPU driver setup
- [llm-gateway](../../networking/llm-gateway/) - Load balancing across vLLM instances
- [llm-cost-optimization](../../../devops/ai/llm-cost-optimization/) - Cost management
- [model-serving-kubernetes](../../../devops/orchestration/model-serving-kubernetes/) - K8s deployment
@@ -0,0 +1,266 @@
---
name: llm-gateway
description: Deploy an API gateway for LLM traffic with load balancing, rate limiting, key management, semantic caching, fallback routing, and cost tracking. Covers LiteLLM Proxy, OpenRouter-compatible setup, and custom Nginx/Traefik patterns.
license: MIT
metadata:
author: devops-skills
version: "1.0"
---
# LLM Gateway
A unified API gateway that routes LLM requests across providers and self-hosted models — with rate limiting, cost tracking, caching, and failover.
## When to Use This Skill
Use this skill when:
- Running multiple LLM backends (OpenAI, Anthropic, vLLM, Ollama) behind a single endpoint
- Enforcing per-team or per-user rate limits and spend budgets
- Implementing automatic fallback when a provider is down
- Adding semantic caching to reduce API costs by 2050%
- Centralizing API key management instead of distributing keys to every app
## Prerequisites
- Docker and Docker Compose
- A PostgreSQL or SQLite database (for LiteLLM state)
- LLM API keys (OpenAI, Anthropic, etc.) or self-hosted vLLM endpoints
- Optional: Redis for caching and rate limiting
## LiteLLM Proxy — Quick Start
LiteLLM is the de facto open-source LLM gateway with OpenAI-compatible API.
```bash
# Run with Docker
docker run -d \
--name litellm-proxy \
-p 4000:4000 \
-e OPENAI_API_KEY=$OPENAI_API_KEY \
-e ANTHROPIC_API_KEY=$ANTHROPIC_API_KEY \
-v $(pwd)/litellm-config.yaml:/app/config.yaml \
ghcr.io/berriai/litellm:main-latest \
--config /app/config.yaml \
--detailed_debug
```
## LiteLLM Configuration
```yaml
# litellm-config.yaml
model_list:
# OpenAI models
- model_name: gpt-4o
litellm_params:
model: openai/gpt-4o
api_key: os.environ/OPENAI_API_KEY
rpm: 10000
tpm: 2000000
- model_name: gpt-4o-mini
litellm_params:
model: openai/gpt-4o-mini
api_key: os.environ/OPENAI_API_KEY
# Anthropic
- model_name: claude-sonnet-4-6
litellm_params:
model: anthropic/claude-sonnet-4-6
api_key: os.environ/ANTHROPIC_API_KEY
# Self-hosted vLLM instances (load balanced)
- model_name: llama-3.1-8b
litellm_params:
model: openai/meta-llama/Llama-3.1-8B-Instruct
api_base: http://vllm-1:8000/v1
api_key: fake # vLLM key
- model_name: llama-3.1-8b
litellm_params:
model: openai/meta-llama/Llama-3.1-8B-Instruct
api_base: http://vllm-2:8000/v1 # second replica — auto load balanced
api_key: fake
# Fallback: cheap model if primary fails
- model_name: gpt-4o
litellm_params:
model: openai/gpt-4o-mini # fallback to cheaper model
api_key: os.environ/OPENAI_API_KEY
router_settings:
routing_strategy: least-busy # or: latency-based, simple-shuffle
num_retries: 3
retry_after: 5
allowed_fails: 2
cooldown_time: 60
# Fallback configuration
fallbacks:
- gpt-4o: [claude-sonnet-4-6]
- claude-sonnet-4-6: [gpt-4o]
litellm_settings:
# Semantic caching
cache: true
cache_params:
type: redis
host: redis
port: 6379
similarity_threshold: 0.90 # cache if >90% semantic similarity
# Logging
success_callback: ["langfuse"]
failure_callback: ["langfuse"]
langfuse_public_key: os.environ/LANGFUSE_PUBLIC_KEY
langfuse_secret_key: os.environ/LANGFUSE_SECRET_KEY
general_settings:
master_key: os.environ/LITELLM_MASTER_KEY
database_url: postgresql://litellm:password@postgres:5432/litellm
store_model_in_db: true
```
## Docker Compose: Full Gateway Stack
```yaml
services:
litellm:
image: ghcr.io/berriai/litellm:main-latest
command: ["--config", "/app/config.yaml", "--port", "4000"]
volumes:
- ./litellm-config.yaml:/app/config.yaml
ports:
- "4000:4000"
environment:
- OPENAI_API_KEY=${OPENAI_API_KEY}
- ANTHROPIC_API_KEY=${ANTHROPIC_API_KEY}
- LITELLM_MASTER_KEY=${LITELLM_MASTER_KEY}
- DATABASE_URL=postgresql://litellm:password@postgres:5432/litellm
depends_on:
postgres:
condition: service_healthy
redis:
condition: service_started
restart: unless-stopped
postgres:
image: postgres:16-alpine
environment:
POSTGRES_DB: litellm
POSTGRES_USER: litellm
POSTGRES_PASSWORD: password
volumes:
- postgres-data:/var/lib/postgresql/data
healthcheck:
test: ["CMD-SHELL", "pg_isready -U litellm"]
interval: 5s
retries: 5
restart: unless-stopped
redis:
image: redis:7-alpine
command: redis-server --maxmemory 2gb --maxmemory-policy allkeys-lru
volumes:
- redis-data:/data
restart: unless-stopped
volumes:
postgres-data:
redis-data:
```
## Virtual Keys & Rate Limiting
```bash
# Create a virtual API key for a team (via LiteLLM API)
curl -X POST http://localhost:4000/key/generate \
-H "Authorization: Bearer $LITELLM_MASTER_KEY" \
-H "Content-Type: application/json" \
-d '{
"team_id": "team-backend",
"key_alias": "backend-team-key",
"models": ["gpt-4o-mini", "llama-3.1-8b"],
"max_budget": 100, # USD limit
"budget_duration": "monthly",
"rpm_limit": 100, # requests per minute
"tpm_limit": 500000 # tokens per minute
}'
# View spend
curl http://localhost:4000/spend/keys \
-H "Authorization: Bearer $LITELLM_MASTER_KEY"
```
## Nginx Load Balancer (Alternative/Complement)
```nginx
# nginx.conf — round-robin across vLLM replicas
upstream vllm_backends {
least_conn;
server vllm-1:8000 max_fails=3 fail_timeout=30s;
server vllm-2:8000 max_fails=3 fail_timeout=30s;
server vllm-3:8000 max_fails=3 fail_timeout=30s;
keepalive 32;
}
server {
listen 80;
server_name llm-api.internal;
# Rate limiting
limit_req_zone $http_authorization zone=per_key:10m rate=100r/m;
limit_req zone=per_key burst=20 nodelay;
location /v1/ {
proxy_pass http://vllm_backends;
proxy_http_version 1.1;
proxy_set_header Connection "";
proxy_set_header Host $host;
proxy_read_timeout 300s; # long timeout for streaming
proxy_buffering off; # required for SSE streaming
proxy_cache_bypass 1;
}
}
```
## Monitoring Gateway Health
```bash
# Check LiteLLM health
curl http://localhost:4000/health
# Model-level health
curl http://localhost:4000/health/liveliness
# Spend by model
curl http://localhost:4000/spend/models \
-H "Authorization: Bearer $LITELLM_MASTER_KEY"
# Active virtual keys
curl http://localhost:4000/key/list \
-H "Authorization: Bearer $LITELLM_MASTER_KEY"
```
## Common Issues
| Issue | Cause | Fix |
|-------|-------|-----|
| `ConnectionRefusedError` to backend | Backend not reachable | Check `api_base` URL; verify backend is healthy |
| Rate limit errors (429) | Budget/RPM exceeded | Increase limits or rotate to fallback model |
| Slow streaming responses | `proxy_buffering` enabled | Set `proxy_buffering off` in Nginx |
| Cache miss rate high | Threshold too strict | Lower `similarity_threshold` to `0.85` |
| Postgres connection errors | DB not ready | Add `depends_on` with `condition: service_healthy` |
## Best Practices
- Use virtual keys per team/app — never expose raw provider API keys.
- Enable `cache: true` with Redis for repeated or similar queries; can cut costs 3050%.
- Set `num_retries: 3` with fallbacks to handle provider outages gracefully.
- Log all requests to Langfuse or OpenTelemetry for cost attribution and debugging.
- Use `least-busy` routing strategy for self-hosted models to avoid GPU saturation.
## Related Skills
- [vllm-server](../../local-ai/vllm-server/) - Backend inference server
- [llm-inference-scaling](../../local-ai/llm-inference-scaling/) - Auto-scaling backends
- [llm-caching](../../../devops/ai/llm-caching/) - Semantic cache patterns
- [llm-cost-optimization](../../../devops/ai/llm-cost-optimization/) - Cost management
@@ -0,0 +1,221 @@
---
name: gpu-server-management
description: Set up and manage NVIDIA GPU servers for AI workloads — driver installation, CUDA toolkit, container toolkit, MIG partitioning, GPU health monitoring, and multi-GPU configuration for LLM inference and training.
license: MIT
metadata:
author: devops-skills
version: "1.0"
---
# GPU Server Management
Provision, configure, and monitor NVIDIA GPU servers for AI inference and training workloads.
## When to Use This Skill
Use this skill when:
- Setting up a new GPU server for LLM inference or model training
- Installing or upgrading NVIDIA drivers and CUDA toolkit
- Configuring Docker with NVIDIA Container Toolkit for GPU workloads
- Partitioning A100/H100 GPUs with MIG for multi-tenant workloads
- Troubleshooting GPU errors, driver issues, or thermal throttling
## Prerequisites
- Ubuntu 22.04 LTS (recommended) or RHEL 8/9
- NVIDIA GPU (A10G, A100, H100, RTX 4090, or L40S recommended)
- Root or sudo access
- Internet access for package downloads
## Driver Installation (Ubuntu)
```bash
# Remove old drivers
sudo apt purge -y 'nvidia*' 'cuda*' 'libcuda*'
sudo apt autoremove -y
# Add NVIDIA package repository
distribution=$(. /etc/os-release; echo $ID$VERSION_ID)
curl -fsSL https://nvidia.github.io/libnvidia-container/gpgkey | \
sudo gpg --dearmor -o /usr/share/keyrings/nvidia-container-toolkit-keyring.gpg
curl -s -L https://nvidia.github.io/libnvidia-container/$distribution/libnvidia-container.list | \
sed 's#deb https://#deb [signed-by=/usr/share/keyrings/nvidia-container-toolkit-keyring.gpg] https://#g' | \
sudo tee /etc/apt/sources.list.d/nvidia-container-toolkit.list
sudo apt update
# Install latest driver (560.x as of 2025)
sudo apt install -y nvidia-driver-560 cuda-toolkit-12-6
# Install NVIDIA Container Toolkit (Docker GPU support)
sudo apt install -y nvidia-container-toolkit
sudo nvidia-ctk runtime configure --runtime=docker
sudo systemctl restart docker
# Verify
nvidia-smi
nvcc --version
docker run --rm --gpus all nvidia/cuda:12.6.0-base-ubuntu22.04 nvidia-smi
```
## Post-Install Configuration
```bash
# Enable persistence mode (reduces driver initialization latency)
sudo nvidia-smi -pm 1
# Set power limit (reduce heat/noise on inference servers)
sudo nvidia-smi -pl 350 # watts; check TDP for your GPU model
# Disable ECC on inference servers (frees ~6% VRAM, less safe)
sudo nvidia-smi --ecc-config=0 # requires reboot
# Enable P2P for multi-GPU NVLink training
sudo nvidia-smi topo -m # check NVLink topology
```
## GPU Health Monitoring
```bash
# Real-time monitoring (like htop for GPUs)
watch -n 1 nvidia-smi
# Detailed stats
nvidia-smi --query-gpu=index,name,temperature.gpu,utilization.gpu,\
utilization.memory,memory.used,memory.free,power.draw,clocks.current.graphics \
--format=csv --loop=1
# DCGM — production monitoring daemon (for clusters)
sudo apt install -y datacenter-gpu-manager
sudo systemctl start dcgm
dcgmi discovery -l # list GPUs
dcgmi diag -r 1 # quick health check
dcgmi diag -r 3 # full diagnostic (takes ~20 min)
# Check GPU errors (XID errors — important for stability)
sudo dmesg | grep -i "NVRM\|nvidia\|XID"
nvidia-smi --query-gpu=ecc.errors.corrected.volatile.total \
--format=csv,noheader
```
## Prometheus GPU Metrics (DCGM Exporter)
```bash
# Deploy DCGM Exporter for Prometheus scraping
docker run -d \
--name dcgm-exporter \
--gpus all \
--cap-add SYS_ADMIN \
-p 9400:9400 \
--restart unless-stopped \
nvcr.io/nvidia/k8s/dcgm-exporter:latest
# Key metrics exposed:
# DCGM_FI_DEV_GPU_UTIL - GPU utilization %
# DCGM_FI_DEV_MEM_COPY_UTIL - Memory bandwidth utilization
# DCGM_FI_DEV_FB_USED - Framebuffer memory used (MB)
# DCGM_FI_DEV_SM_CLOCK - SM clock speed (MHz)
# DCGM_FI_DEV_GPU_TEMP - Temperature (°C)
# DCGM_FI_DEV_POWER_USAGE - Power draw (W)
# DCGM_FI_DEV_XID_ERRORS - XID error count (0 = healthy)
```
## MIG Partitioning (A100/H100)
MIG (Multi-Instance GPU) allows slicing one GPU into isolated smaller GPUs.
```bash
# Enable MIG mode (requires reboot or restart of all processes)
sudo nvidia-smi -mig 1
sudo systemctl restart nvidia-persistenced
# List available MIG profiles (A100 80GB example)
nvidia-smi mig -lgip
# 1g.10gb — 1 slice, 10GB (max 7 instances)
# 2g.20gb — 2 slices, 20GB (max 3 instances)
# 3g.40gb — 3 slices, 40GB (max 2 instances)
# 7g.80gb — full GPU, 80GB (max 1 instance)
# Create MIG instances (e.g., 3× 2g.20gb + 1× 2g.20gb = multi-tenant)
sudo nvidia-smi mig -cgi 2g.20gb,2g.20gb,2g.20gb,2g.20gb -C
# List created instances
nvidia-smi mig -lgi
nvidia-smi mig -lcgi
# Use in Docker
docker run --gpus '"device=MIG-GPU-xxx/0/0"' ...
# Disable MIG
sudo nvidia-smi mig -i 0 -dci
sudo nvidia-smi mig -i 0 -dgi
sudo nvidia-smi -mig 0
```
## Kernel & OS Tuning for GPU Servers
```bash
# Increase file descriptor limits
echo '* soft nofile 1048576' | sudo tee -a /etc/security/limits.conf
echo '* hard nofile 1048576' | sudo tee -a /etc/security/limits.conf
# Disable transparent huge pages (reduces latency jitter)
echo never | sudo tee /sys/kernel/mm/transparent_hugepage/enabled
echo never | sudo tee /sys/kernel/mm/transparent_hugepage/defrag
# Persist via rc.local or systemd unit:
cat <<'EOF' | sudo tee /etc/rc.local
#!/bin/bash
echo never > /sys/kernel/mm/transparent_hugepage/enabled
echo never > /sys/kernel/mm/transparent_hugepage/defrag
nvidia-smi -pm 1
exit 0
EOF
sudo chmod +x /etc/rc.local
# PCIe performance mode
sudo nvidia-smi --auto-boost-default=0
sudo nvidia-smi --auto-boost-permission=0
```
## Multi-GPU Topology Check
```bash
# Check NVLink and PCIe topology
nvidia-smi topo -m
# Output shows interconnect type:
# NV4 = NVLink 4.0 (H100 SXM)
# NV2 = NVLink 2.0 (A100 SXM)
# PHB = PCIe bus (slower; avoid for tensor parallel training)
# PIX = same PCIe switch (fast)
# Bandwidth test between GPUs
/usr/local/cuda/samples/bin/x86_64/linux/release/p2pBandwidthLatencyTest
```
## Common Issues
| Issue | Cause | Fix |
|-------|-------|-----|
| `nvidia-smi: command not found` | Driver not installed | Follow driver installation steps above |
| Driver version mismatch | CUDA/driver incompatibility | Check compatibility matrix at developer.nvidia.com |
| GPU temperature >85°C | Poor airflow or fan failure | Check `nvidia-smi -q -d TEMPERATURE`; reseat cooler |
| XID 79 errors | GPU hardware error | Run `dcgmi diag -r 3`; may need GPU replacement |
| `failed to open device` in container | Container toolkit not configured | Run `nvidia-ctk runtime configure --runtime=docker` |
| Low PCIe bandwidth | Wrong slot or power limit | Check `nvidia-smi -q | grep PCIe`; use x16 slot |
## Best Practices
- Always enable persistence mode (`nvidia-smi -pm 1`) — reduces first-request latency.
- Monitor XID errors; persistent XID 79/94 indicates hardware failure.
- For training: use NVLink-connected GPUs; for inference: PCIe is usually fine.
- Set up DCGM alerts on temperature >80°C and power draw near TDP.
- Use MIG for multi-tenant inference to provide GPU isolation between models.
## Related Skills
- [vllm-server](../../local-ai/vllm-server/) - LLM inference on GPUs
- [llm-fine-tuning](../../local-ai/llm-fine-tuning/) - GPU training setup
- [linux-hardening](../../../security/hardening/linux-hardening/) - Secure the host OS
- [prometheus-grafana](../../../devops/observability/prometheus-grafana/) - Metrics dashboards