Scaling AEM Dispatcher servers for frequent client library invalidation
Reducing the invalidation interval for client libraries in AEM (for example, from several hours to a few minutes) can help minimize 404 errors and UI issues caused by stale or missing assets. However, this change increases the frequency of cache invalidations, which can lead to higher load on Dispatcher servers. If server capacity is not adjusted accordingly, end users experience degraded performance or UI issues. This article explains how to address increased load on Adobe Experience Manager (AEM) Dispatcher servers and outlines steps to ensure stable performance.
Description description
Environment
- Adobe Experience Manager (all versions)
- Dispatcher servers in production environments
Issue/Symptoms
- Increased CPU, memory, or network utilization on Dispatcher servers
- UI issues reported by end users
- 404errors previously observed due to stale or missing client libraries
Cause
Reducing the client library invalidation interval increases the frequency of cache invalidations, resulting in higher load on Dispatcher servers. Without sufficient server resources, this can impact site performance and user experience.
Resolution resolution
To fix the frequent client library invalidation issue, follow these steps:
- Monitor Dispatcher server performance by tracking CPU, memory, and network utilization on all Dispatcher servers after reducing the client library invalidation interval and reviewing Dispatcher and web server logs for signs of resource exhaustion or performance bottlenecks.
- Assess server capacity by comparing observed resource usage against current server or VM specifications and determining whether the current configuration is sufficient to handle the increased load.
- Increase server capacity as needed by evaluating whether resource usage is consistently high or performance issues are observed, increasing the server or VM size for all affected Dispatcher instances.
- Choose a configuration appropriate for your deployment and cloud provider environment, and apply the new configuration to all relevant Dispatcher nodes in the production environment.
- Validate environment stability by continuing to monitor Dispatcher performance after upsizing and confirming that UI issues and 404 errors are reduced or resolved.
- Perform ongoing monitoring by regularly reviewing Dispatcher server metrics and adjusting capacity if further increases in load are observed.