LLM Systems Architecture 2025

Technical overview of modern LLM system architectures, focusing on inference, fine-tuning, and system integration.

When deploying LLMs in production, teams face a critical decision: build custom MLOps infrastructure or leverage managed service providers. Building in-house offers maximum control and potential cost savings at scale but requires significant DevOps expertise and ongoing maintenance. Managed services provide faster time-to-market and reduced operational complexity but may have higher per-token costs and vendor lock-in concerns. This guide covers core architectural components relevant to both approaches, helping teams make informed decisions based on their scale, expertise, and requirements.

System Components

The foundation of any LLM system requires careful consideration of these core architectural elements, each playing a crucial role in system performance and reliability.

ComponentImplementationPurpose
ServingDisaggregatedResource optimization
CachingSemantic-basedReduce redundant compute
ProcessingBatch operationsGPU utilization
DeploymentServerlessDynamic scaling

Advanced Inference Optimizations

Modern LLM deployments leverage several key optimization techniques to balance throughput, latency, and resource utilization. These approaches can significantly impact both performance and operational costs.

TechniqueDescriptionTrade-offs
Semantic CachingStores semantically similar queries/responsesMemory vs compute cost, cache invalidation complexity
Speculative DecodingPredicts multiple tokens simultaneouslyHigher GPU memory usage, potential wasted compute
KV Cache ManagementEfficient context window handlingMemory vs performance balance
Continuous BatchingDynamic request combiningLatency vs throughput optimization

Model Management

Effective model management becomes critical as organizations scale their LLM operations. This encompasses everything from initial training to deployment and monitoring.

FeatureImplementationConsideration
Fine-tuningLoRA-basedMemory efficiency
VariantsVersion controlDeployment management
InferenceBatched servingResource allocation
MonitoringUsage metricsCost optimization

Enterprise Requirements

Enterprise deployments demand additional considerations beyond basic functionality. These requirements ensure production readiness and compliance with organizational standards.

CategoryFeaturesPurpose
SecuritySOC2, HIPAACompliance
NetworkVPC/VPNIsolation
ScalingAuto-scalingResource management
MonitoringAnalyticsPerformance tracking

Implementation Notes

When moving from development to production, teams often encounter several common challenges. Understanding these challenges and their solutions helps prevent operational issues.

ChallengeSolutionCommon Pitfalls
Context LengthToken chunkingExceeding GPU memory, losing context between chunks
Cost ControlRequest batching, cachingRedundant API calls, inefficient prompt design
Error HandlingGraceful fallbacksMissing retry logic, timeout handling
Rate LimitsQueue managementInsufficient backoff, missing circuit breakers

Resource Planning (MLOps)

For teams building their own MLOps infrastructure, resource planning is crucial. These metrics provide baseline guidance for infrastructure provisioning.

ResourceTypical UsageOptimization
GPU VRAM8-80GB per modelLoad balancing, model quantization
Network50-500ms latencyRequest batching, edge caching
Storage10-100GB per modelLazy loading, pruning
Memory16-64GB RAMStreaming responses, garbage collection

Development Tools

A robust tooling ecosystem supports successful LLM deployments. These tools help teams monitor, optimize, and maintain their systems effectively.

CategoryExamplesUse Case
MonitoringPrometheus, GrafanaPerformance tracking
ProfilingPyTorch Profiler, nsightOptimization
TestingLLM Unit TestsOutput validation
DeploymentDocker, K8sOrchestration

The architecture supports multiple modalities (text, audio, image) and integrates with external tools through standardized APIs. Implementation focuses on maintainable, scalable systems rather than raw performance metrics.