Scaling Game Servers: Best Practices for High-Traffic Events | Retranex Blog

Are you aware that big game releases can experience player numbers explode from not a single soul in sight to millions joining in only a handful of hours? When the Fortnite platform hosted its Travis Scott in-game concert, over 12.3 million concurrent participants took part in a single event, shattering previous records set by anything else. Events of this nature give game server infrastructure the kinds of challenges that require a ton of meticulous planning, a dash of game server optimization magic, and a miracle or three to pull off. Otherwise, your game's player experience is about to take a nosedive.

The reputation of a game in the current competitive gaming market can hinge on its server's performance. Players demand that seamless experience it doesn't matter whether you're the only one playing or the game's a simultaneous event for thousands of players. Yet for game servers, this is the kind of pressure that can turn total commitment and even a few minutes of downtime into negative reviews and a lost player base.

This article examines core tactics for efficiently multiplying your game servers during peak times when lots of users are online—everything from gearing up ahead of time with copious amounts of resources to making smart changes during the event when it's clear that lots of users are online and, finally, postmorteming and figuring out what worked, what didn't, and how to better tweak things for next time.

Understanding Server Performance During High-Traffic Events

In online gaming, server performance is gauged by three key factors: response time, stability, and throughput. These measures are bound to affect how players perceive their performance through elements like lag, server instability, and drop rate.

The challenges that arise due to game launches and special events can be attributed to the following factors:

Sudden player surges: Unlike gradual growth, launches and events create immediate demand spikes
Unpredictable patterns: Player behavior during new events can be difficult to model in advance
Geographic concentration: Regional events may create localized server pressure
Feature-specific load: New game modes or mechanics may stress specific server components

Real-time monitoring becomes especially crucial during these periods. Key metrics to track include:

Utilization of server CPU and memory
Consumption of network bandwidth
Rates of connection and requests for authentication
Performance of database queries and lengths of queues
Health of instances across your infrastructure

Modern monitoring solutions like Prometheus, Grafana, and specialized game server monitoring tools allow developers to detect potential issues before they affect players and respond proactively to changing conditions.

Effective Server Provisioning Techniques

Today's cloud infrastructure offers powerful tools for dynamic resource allocation, making it possible to provision just the right amount of resources for the successful management of high-traffic events.

Leveraging Cloud Scalability

Gaming-specific services provided by cloud platforms such as AWS, Google Cloud, and Azure are designed for elastic workloads. These services include but are not limited to the following:

Deployments in containers: Using Kubernetes or platforms for fast scaling across multiple instances of containers.
Distributing geographically: Deploying across several locations to ensure load distribution even under stress.
Hybrid solutions: Using a combination of dedicated machines and the cloud in such a way as to minimize costs.

Auto-scaling Strategies

To successfully achieve auto-scaling, there are some things to consider and configure first deliberately. These things and configurations help achieve desired outcomes.

Predictive scaling: Using historical data and AI models to predict resource needs
Threshold-based scaling: Setting specific performance metrics that trigger scaling events
Warm pools: Maintaining partially-initialized instances ready for immediate deployment
Scheduled scaling: Pre-provisioning resources based on announced event times

One principal MMORPG employs a pre-warming plan in which it systematically increases server capacity in the 48 hours leading up to a major content release. This scaled-up strategy, following patterns observed from previous launches.

Event-Specific Provisioning

For known events, consider allocating critical resources needed to handle a projected 30 to 50 percent more than the maximum expected demand during peak times.

Setting up a queuing system to handle user authentication when things get really busy
Turning off some non-essential features
Making sure that operational and developmental teams talk to each other—especially when something's gone wrong

Numerous studios put into effect "emergency provisioning plans" as well that can be executed on short notice when metrics indicate resource exhaustion is about to happen during an event.

Best Practices for Server Optimization

Even when you have enough resources, optimization is still very important for making the most of your infrastructure's capacity. Given that all infrastructure serves some kind of workload, the design of both the workloads and the infrastructure itself need to take optimization into account.

Load Balancing Techniques

Contemporary load balancing encompasses far more than just the basic round-robin technique. It operates dynamically, allocating work based on real-time assessments of server conditions. When a user first connects to a server, dynamic load balancing ensures that all requests from that user are sent to the same server. Otherwise, the state of the user's session could be lost, and the user would experience the server as dysfunctional.

Contemporary load balancing goes a long way toward making the cloud appear to the user as a single coherent entity, capable of serving all requests.

Dynamic load balancing: Routing players based on server load rather than strict allocation
Session persistence: Keeping players on the same servers when possible to reduce state transfer
Geographic balancing: Directing players to physically closer servers to reduce latency
Microservice distribution: Balancing different game services independently across your infrastructure

It's also a good idea to establish health checks that identify decrepit instances and reroute traffic away from them can avert cascading failures at peak times.

Caching Strategies

The load on servers is reduced significantly by strategic caching:

Content Delivery Networks (CDNs): Delivering static assets and game updates across the globe
Database query caching: Storing the results of frequently repeated queries for reduced latency and increased throughput
In-memory data stores: Using Redis (or a similar solution) as an in-memory database for all data that needs to be accessed and altered quickly
Client-side caching: Storing relevant state information on the client for access without hitting the server.

An AAA game developer cut their database load by 65% during a large expansion release by using a tiered caching strategy that focused on the player actions most often taken. When paired with some optimizations in the database that housed their player data, this change resulted in a much smoother experience for players during the release period.

Database Optimization

When high traffic occurs, databases frequently become bottlenecks.

Connection pooling: Efficient management of database connections, reducing overhead
Query optimization: Changing the structure of the query so that it will minimize runtime
Sharding: Distributing the database load across several servers
Read replicas: Different instances of the database handle either read or write operations.
NoSQL solutions: Using specialized databases for specific workloads.

Think about putting in place circuit breakers that can, during times of extreme load, protect your database by degrading nonessential features.

Testing and Stress-Testing Your Servers

There is no scaling strategy that does not include rigorous testing.

Pre-Event Testing Methodologies

Simulating realistic conditions is required for effective testing.es simulating realistic conditions:

Gradual load testing: Incrementally increasing simulated players to identify scaling limits
Spike testing: Introducing sudden player surges to test auto-scaling response times
Component testing: Isolating specific services to identify individual bottlenecks
Regional testing: Verifying performance across different geographic deployments

Game-specific testing tools often provide more accurate results than generic load testing solutions, as they can simulate actual game client behavior rather than simple HTTP requests.

Simulation Techniques

Leading-edge testing methods include:

Bot players: Automated clients that simulate typical player behavior
Replay systems: Using recorded actions of real players to set up realistic test scenarios
Chaos engineering: Systematically introducing failures to test system resilience
Blue/green deployments: Testing new configurations on duplicate infrastructure

Very often, leading studios hold "public test realm" events. These events are excellent marketing opportunities. They also serve as real load tests, providing the kind of action that makes systems sweat.

Iterative Optimization

Testing should proceed according to a cycle of continuous improvement.

Establish baseline performance metrics
Identify bottlenecks through testing
Implement specific optimizations
Re-test to measure improvement
Document findings for future events

This step-by-step method develops organizational know-how that enhances your team's capability to tackle scaling problems in the future.

Post-Event Analysis and Continuous Improvement

The event's conclusion does not bring work to an end:

Data Collection and Analysis

Comprehensive examinations of the post-mortem should consider:

Metrics of how systems performed versus expectations.
Efficiency of scaling: Were resources used appropriately?
Failure points and performance of any components that had problems.
Cost and financial impact of your scaling strategy.
Data on player experience and the impact of the above on retention and feedback.

Numerous teams put together "scaling retrospectives" that capture not only the technical aspects of performance but also the business effects resulting from each significant event.

Feedback Loops

Understanding player feedback is crucial for effective game development. Players looking for a particular experience will give you that lighting insight. The better the game, the better the feedback from players. Make use of the feedback, but understand that it might be a push in one direction or the other.

Monitoring social media: Keeping a careful watch on players' real-time moods during events
Tracking support tickets: Pinpointing the 1 or 2 issues that almost all players seem to be hitting
Engaging with the community: Asking players for feedback in game forums and Discord
Examining telemetry data: Looking at at the disconnections, latency spikes, and other technical things that show some players are having a bad time

One indie studio says their rapid growth can be credited to a player-first scaling philosophy where they prioritize optimizing efforts based directly on player feedback after each content release.

Long-term Strategies

Sustainable improvement requires long-term thinking:

Evolution of infrastructure: Moving progressively towards architectures that are more scalable.
Reducing technical debt: Dealing with fundamental problems that restrict growth
Building up institutional memory around scaling events: Documentation and pooling knowledge.
Training team: Gaining the know-how to manage a busy situation successfully.

Several major studios have adopted the concept of a "Scaling Calendar". These are regular optimization sprints that are spread throughout the year and used to maintain continuously evolving infrastructure toward a set of major releases.

Conclusion

Scaling a game server successfully through high-traffic times needs a thorough understanding of basic performance principles, along with good strategies for server provisioning, effective optimization, and exhaustive pre- and post-event testing and analysis.

If game developers and infrastructure teams follow these best practices, they can ensure that players have unforgettable experiences, even during the sorts of intense launch events and special promotions that put a game's online services to the test.

This article was prepared by the Retranex infrastructure team, who specialize in game server hosting and optimization for developers of all sizes.