LLM Training
Process of training large language models by optimizing model parameters on large datasets toward defined learning objectives.
Classification
- ComplexityMedium
- Impact areaOrganizational
- Decision typeOrganizational
- Organizational maturityIntermediate
Technical context
Principles & goals
Use cases & scenarios
Compromises
- Data leakage leads to overstated performance and compliance risks
- Bias and toxic content can distort behavior and outputs
- Insufficient safety testing increases misuse and reputation risk
- Strict data hygiene: deduplication, leakage checks, PII filtering
- Reproducible runs with deterministic seeds and versioning
- Multi-stage evaluation: quality, safety, robustness, cost
I/O & resources
- Training data, data licenses, and data pipeline
- Compute (GPU/TPU), training stack, and configuration
- Target metrics, evaluation suite, and safety policies
- Model checkpoints and release artifacts
- Evaluation reports and regression analyses
- Documentation, audit, and compliance artifacts
Description
LLM training refers to the process of building or improving a large language model by optimizing its parameters on large text and, optionally, multimodal datasets. It includes dataset selection and preparation, objective definition, running pretraining and fine-tuning (e.g., supervised fine-tuning), and iterative evaluation. Additional steps such as alignment (e.g., preference optimization) and safety and quality checks are often integrated to achieve desired behavior, robustness, and compliance. Effective LLM training requires reproducible pipelines, clear metrics, controlled experimentation, and awareness of risks such as data leakage, bias, hallucinations, and cost.
✔Benefits
- Improved task performance and domain coverage through targeted training
- More consistent behavior via alignment and policy constraints
- Measurable quality improvements through systematic evaluation
✖Limitations
- High cost for compute, data preparation, and iteration
- Results strongly depend on data quality and objective definition
- Training can introduce regressions and new failure modes
Trade-offs
Metrics
- Loss/Perplexity
Training and validation metrics for convergence and generalization.
- Task Benchmarks
Comparable metrics on defined task and evaluation suites.
- Safety and Policy Compliance
Meeting safety criteria and policies via tests and red-teaming.
Examples & implementations
SFT for code assistance
A base model is fine-tuned on prompt/response pairs for coding tasks and regression-tested against an evaluation suite.
Continued pretraining for domain language
A model is further pretrained on curated domain documents to better handle terminology and style.
Alignment with preference data
A model is aligned via preference optimization toward helpful and safer behavior and validated with safety benchmarks.
Implementation steps
Define goals, metrics, policies, and evaluation suite
Curate, deduplicate, filter, and version data
Run training (pretraining/fine-tuning) with checkpoints
Run evaluation, safety tests, and regression checks
Establish release, deployment, monitoring, and iteration
⚠️ Technical debt & bottlenecks
Technical debt
- Unversioned datasets and missing reproducibility
- Missing model registry and unclear release artifacts
- Ad-hoc evaluations without durable benchmark suites
Known bottlenecks
Misuse examples
- Training on sensitive or proprietary data without rights clearance
- Using training data that contaminates evaluation or benchmarking
- Releasing a model without safety validation into production contexts
Typical traps
- Data leaks due to overlap across train/validation/test
- Poor generalization due to overfitting on curated samples
- Cost explosion due to uncontrolled experimentation
Required skills
Architectural drivers
Constraints
- • Compute budget and runtime limits
- • Data rights, licensing, and privacy
- • Reproducibility and auditability of training runs