Basic Control
Excl:*global-gc-behavior*
- :auto - gc automatically after exceeding threshold (excl:*tenured-bytes-limit*)
- :warn - warning only after exceeding threshold
- :auto-and-warn - warning and gc after exceeding threshold
- nil - no warnings and no gc
- (300 2.0) - gc after
- threshold is exceeded and lisp is idle 300 seconds
- 2.0 times threshold is exceeded