Citrix Server Input Delay Test

Poor application performance is one of the most difficult problems to diagnose by the administrators. Traditionally, diagnosis was done by collecting CPU, memory, disk I/O and a few other metrics. The data collected from traditional metrics were not sufficient to figure out the root cause of poor performance of the applications since the variations measured by the metrics were large. In virtual environments where multiple users accessed an application from remote at the same time, users faced difficulties in accessing the application whenever there was an increase in the count of users. The more the users are accessing the application, the higher was the CPU usage of the systems in the environment and the higher was the user input delays i.e., the users were forced to wait for a longer duration to interact with the application. The user input delay is measured by how long any user input (such as mouse or keyboard usage) stays in the queue before it is picked up by a process. To aid in figuring out the real reason behind such poor show put up by the applications from the perspective of user experience, it is necessary to measure the user input flows or rather user input delays while the applications were accessed.

This test captures such user input delays at the Citrix Virtual Apps server level and reports the same to the administrators. With the help of this test, administrators can determine the maximum and average time taken by the applications to respond to the user input across all Virtual Apps sessions, and thus figure out if there is any time delay in responses from applications.


This test will report measures only on Windows 2019 (and above).

Target of the test : A Citrix Virtual Apps 7.x Server

Agent deploying the test : An internal agent

Outputs of the test : One set of results for the target Citrix Virtual Apps server being monitored

Configurable parameters for the test
  1. TEST PERIOD – How often should the test be executed
  2. Host – The host for which the test is to be configured
  3. Port Refers to the port used by the Citrix Virtual Apps server. By default, this is set to 1494.
Measurements made by the test
Measurement Description Measurement Unit Interpretation

Maximum input delay for sessions

Indicates the maximum amount of time lag detected between the user's input through any input device (e.g., mouse, keyboard) and the time at which the application responds to the input.


Ideally, the values of these measures should be 0 or very low.

To know exactly which user/application experiences the maximum input lag, you can refer to the Citrix Users in Sessions and Citrix Applications tests.

Average input delay for sessions

Indicates the average amount of time lag detected between the user's input through any input device (e.g., mouse, keyboard) and the time at which the application detected the input.