Highload 0. Введение

Course overview

Goal: teach you to think like an architect — not to train on specific tools or one-off configurations.

• Duration and format
  • Introductory high-load systems architecture course, 6 months.
  • Weekly morning sessions, regular homework (client questionnaires, project scoping), group chat for coordination, hands-on tasks and reviews.
  • Main practical activity: team projects and an exam where teams present and justify architectures.
• Focus and learning objectives
  • Emphasis on architectural thinking, principles and trade-offs rather than on particular stacks.
  • Combines theory (≈20 architectural patterns) with practical design exercises and iteration.
• Target audience
  • Aspiring techies, backend developers, team leads, architects, technical directors.
  • Also useful for project/product managers who need a deeper technical understanding.

Instructor background

• Instructor: Oleg Bunin — entrepreneur and former web / high-load systems developer.
• Relevant experience: projects for major Russian sites (sports.ru, RIA Novosti), Olympic projects, and early consulting for Pavel Durov.
• Also organizes developer conferences.

High-level teaching approach

• Emphasis on principles, trade-offs and architectural thinking rather than brand-new tools.
• Architects must understand internal server, network and cloud behavior and be able to choose tools according to constraints.
• Practical cycle:
  1. Learn patterns.
  2. Apply them to a concrete project (example: a tourist social network).
  3. Break and redesign the system.
  4. Present and justify the solutions.

Key technical concepts and topics covered

• System decomposition and component selection
  • Splitting functionality (storage, streams, media, metadata, etc.).
  • Choosing tooling per component.
• Data storage patterns
  • Handling large volumes and binary data (images, videos).
  • Sharding strategies and metadata placement.
  • Incremental migration strategies (e.g., write new data to new servers vs move old data).
  • Archival vs deletion decisions.
• Scaling and load distribution
  • Load balancing and horizontal scaling limits.
  • When and why to split services.
  • Cloud limitations — cloud is not a panacea; understand internal constraints.
• Networking fundamentals
  • DNS resolution, IP addressing, packetization, network cards, OS network stack.
  • Ports (80/443) and the 7-layer OSI model as a base mental model.
• Web server and request processing
  • Connection handling and multithreaded servers.
  • Handing requests to application logic (CGI vs persistent processes).
  • Buffering vs streaming responses and implications for latency and resources.
• Backend performance and bottlenecks
  • Database call latency and imbalance between layers.
  • Monitoring and detecting slow components.
• Caching and cache invalidation
  • OS-level caching, HTTP caching headers, CDN/edge caches.
  • Asset versioning strategies (query strings vs file renaming) to force updates.
• Frontend behavior
  • Roles of HTML/CSS/JS; browser parsing and asset loading limits (concurrent connections).
  • JavaScript-driven dynamic updates: AJAX, long-polling, streams, WebSockets.
  • Segmented video streaming (small chunk delivery).
• Security and robustness
  • How buffering and response strategies affect DoS resistance.
  • Monitoring and consideration of network intermediaries (caches, filters).
  • Designing for censorship resistance and handling national filtering (e.g., Roskomnadzor / SORM).
• Tools and diagnostics
  • Browser developer tools (network inspector).
  • Traceroute / path analysis to inspect routing and intermediate caches.
  • OSI model references.

Project management and product considerations

• Importance of scoping
  • Compile detailed questionnaires for clients to collect product requirements, access patterns and non-functional needs.
• Trade-offs
  • Translate product wishes into realistic implementation plans, balancing desires and feasibility.
• Storage lifecycle decisions
  • What to store, archive or delete depends on access patterns (e.g., news feed vs personal posts) and affects architecture.

Course exercises and evaluation

• Practical design assignments, examples:
  • Image storage sharding.
  • Feed architecture.
  • Censorship-resistant delivery.
• Team exam
  • Given a project, teams design an architecture and must explain trade-offs and rationale (no single correct answer).
• Iteration and critique
  • Frequent iteration, critique and guided redesign to build architectural thinking.

Career guidance

• Typical career path: individual contributor → team lead → architect → technical director.
• Architects focus on systems and processes; they are in high demand and well-paid.
• The course aims to prepare engineers to move into architectural roles.

References and recommended tools

• OSI 7-layer model (one-page summary on Wikipedia).
• Browser developer tools (Network tab).
• Traceroute / path analysis utilities.
• Practical guides on caching and asset versioning.

Main speaker / sources

• Oleg Bunin — course instructor, entrepreneur and high-load systems practitioner (experience with sports.ru, RIA Novosti and early consulting for Pavel Durov).