VSC FAQ: Performance

Calibre/Simulations are running slowly

Delays running simulations, Calibre and other external applications

If GDM is active during external applications that access the Cadence database, those operations may be significantly slower due to the activity associated with GDM.

For most applications, GDM can be disabled by setting the environment variable GDMNOTLOAD to 1.

For applications run from inside Virtuoso, GDMNOTLOADLIB can be set in a wrapper script which then calls the application.