What are some best practices for caching and scaling WMS services?

1 Use tile caching

Tile caching is the process of pre-generating and storing map images in fixed sizes and resolutions, called tiles. Tile caching reduces the load on your server and network, as well as the response time for your clients. You can use a dedicated tile server, such as GeoServer or MapServer, or a third-party service, such as Mapbox or ArcGIS Online, to create and serve your tiles. You can also use a web map client, such as OpenLayers or Leaflet, to request and display your tiles.

2 Configure cache expiration

Cache expiration is the mechanism that determines how long your tiles are valid and when they need to be refreshed. Cache expiration can be based on time, events, or dependencies. You should configure your cache expiration according to the frequency and nature of your data updates. For example, if your data changes daily, you can set your cache expiration to 24 hours. If your data depends on another source, you can use a trigger or a notification to invalidate your cache.

3 Optimize your styles and filters

Styles and filters are the parameters that define how your data is rendered and filtered on the map. Styles and filters can affect the performance and quality of your WMS requests, as they can increase the complexity and size of your map images. You should optimize your styles and filters by using simple and consistent rules, avoiding unnecessary or redundant expressions, and applying generalization and simplification techniques. You should also avoid using dynamic or user-defined styles and filters, as they can prevent your tiles from being cached.

4 Scale your infrastructure

Scaling your infrastructure is the process of adjusting your resources and capacity to meet the demand and load of your WMS services. Scaling can be done horizontally or vertically. Horizontal scaling involves adding more servers or nodes to your system, which can increase your throughput and availability. Vertical scaling involves upgrading your existing servers or nodes, which can increase your performance and efficiency. You should scale your infrastructure according to your traffic patterns, service level agreements, and budget constraints.

5 Use load balancing and clustering

Load balancing and clustering are the techniques that distribute your requests and workload among multiple servers or nodes in your system. Load balancing and clustering can improve your scalability, reliability, and fault tolerance. You can use a load balancer, such as Nginx or Apache, or a cluster manager, such as ZooKeeper or Kubernetes, to manage your load balancing and clustering. You should configure your load balancing and clustering to balance your load evenly, handle failures gracefully, and synchronize your cache across your nodes.

6 Monitor and test your services

Monitoring and testing your services are the activities that measure and evaluate the performance, functionality, and quality of your WMS services. Monitoring and testing can help you identify and troubleshoot issues, optimize your configuration, and ensure your user satisfaction. You can use tools, such as GeoHealthCheck or QGIS, or services, such as New Relic or Pingdom, to monitor and test your services. You should monitor and test your services regularly, using realistic scenarios and metrics, and reporting and acting on the results.

7 Here’s what else to consider

This is a space to share examples, stories, or insights that don’t fit into any of the previous sections. What else would you like to add?