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AR# 60164

Licensing - Vivado License Manager (VLM) takes a long time to load the available licenses


On opening Vivado License Manager (VLM), it takes a long time (minutes) to detect and show the licenses that are found.

Additionally, refreshing the view, copying a new license, or setting one of the license variables requires me to wait again to see the available licenses.


Although Xilinx is continuing to evaluate ways to speed the loading of licenses in VLM, the license loading time is determined by the depth of the Xilinx license search tree, the number of licenses or locations searched, and the speed of the network connections to the floating licenses. 

Because VLM needs to show all available license features, it is required to look in every directory, license, and PORT@SERVER location that appears in the license search path.

Typically, PORT@SERVER locations with many licenses slows the VLM loading the most. 

To speed up loading, we recommend the following: 

  • Only Use XILINXD_LICENSE_FILE to point to Xilinx specific licenses.  Do the same for other vendors (using the vendor specific license variable) and unset the LM_LICENSE_FILE variable.
  • Remove any unused PORT@Server locations from the XILINXD_LICENSE_FILE and LM_LICENSE_FILE variables.
  • Remove redundant PORT@Server locations from the XILINXD_LICENSE_FILE and LM_LICENSE_FILE variables.
  • Remove expired or unused licenses from the default license directories and any directories pointed to by: XILINXD_LICENSE_FILE and LM_LICENSE_FILE variables.

VLM looks for license keys in the following places in order:

  • All of the places listed by the environment variable XILINXD_LICENSE_FILE, if set.
  • Location cached for XILINXD_LICENSE_FILE in the registry (HKLM\Software\FLEXlm License Manager) for Windows, or registry file ($HOME/.flexlmrc) for Linux.
  • All the places listed by the environment variable LM_LICENSE_FILE, if set.
  • %HOMEDRIVE%\.Xilinx\*.lic or $HOME/.Xilinx/*.lic
  • %HOMEDRIVE%\.Xilinx\Coregen\CoreLicenses\*.lic or $HOME/.Xilinx/Coregen/CoreLicenses/*.lic
  • %XILINX_VIVADO%/data/ip/core_licenses/*.lic (for each entry in %XILINX%) 
AR# 60164
Date Created 04/07/2014
Last Updated 04/15/2014
Status Active
Type General Article
  • Vivado Design Suite