Recognizing some common performance problems

The following lists common performance issues which occur, together with proposals on how to spot and counteract them.

Table 1. Recognizing common performance problems

AreaSymptom(s)To increase capacity...To reduce volume...
ClientHigh client CPU usage.Install a client CPU with higher performance.Simplify (HTML) layout.
 Low server CPU usage.Upgrade to a faster browser.Improve client-side cache.
 Some clients fast, some slow.  
Server   
NetworkCPU usage low on both servers and clients.Remove any network bottlenecks.Improve/optimize the configuration of the client cache.
 Browsing locally on the server is (comparatively) fast.Increase network bandwidth.Reduce the "weight" of your web pages (e.g. less images, optimized HTML).
Web-serverCPU usage on the web-server is high.Cluster your web-servers.Reduce the hits per page (visit).
  Use a hardware load-balancer. 
ApplicationServer CPU usage is high.Cluster your CQ5 instances.Search for, and eliminate, CPU and memory hogs (use code review, timing output, etc).
 High memory consumption. Improve caching on all levels.
 Low response times. Optimize templates and components (e.g. structure, logic).
Repository   
Cache