




To control the actions of the garbage collector, use the symbols 
avoid-gc
, 
get-gc-parameters
, 
gc-if-needed
, 
mark-and-sweep
, 
normal-gc
, 
set-gc-parameters
, 
without-interrupts
 and 
with-heavy-allocation
. 
To control expansion, use  
enlarge-generation
.
To control fragmentation, use 
check-fragmentation 
with 
try-move-in-generation 
or 
try-compact-in-generation
.