Performance Hits and Slow Login on Citrix Devices

Products

• Carbon Black App Control (formerly Cb Protection)

Issue/Introduction

• Slower than average login times on Citrix terminal servers
• Longer than average load time on opening application on initial login

Environment

• App Control Agent: All Supported Versions
• Citrix Enterprise Products

Cause

Citrix servers tend to have larger than average numbers of operations when configuring logins. These larger number of operations means more items that need verified. 

Resolution

1. Upgrade to Agent 8.9.4+ to take advantage of the latest performance improvements.

   EP-19006: Fixed a small memory leak that occurred any time a Yara file analysis was started on the agent. 
   EP-18263: Fixed a small leak of OS synchronization objects that can result in high memory utilization issues on long-running systems.
   EP-17440: Significantly improved the performance of rule expansion, by reducing the amount of file IO done during name normalization. 
             Since rule expansion is performed when a new user logs in, significant performance gains should be seen in multi-user environments.
   

2. Implement the Agent Config to disable reevaluate_on_logon.
3. Implement the Agent Config to disable the startup Cache Consistency Check.
4. Follow the guidance for Citrix Best Practices as outlined in the attached PDF.
5. Follow the correct procedure for creating a Template Computer to use for Citrix Clones.
   • It is critical that the Golden Image shows Initialization as Complete and File Synchronization at 100% before shutting down & saving.
   • Any remaining Initialization, Synchronization, or other activity will happen on EVERY Clone that is started, EVERY time, which will cause performance issues.