The macro with-heavy-allocation
is for use with code that allocates a lot of space but is not interactive. It ensures that garbage collection (GC) is carried out less frequently while these forms are being executed. However, each GC may take longer.
In LispWorks 5.0 with-heavy-allocation
is implemented only in 32-bit LispWorks. In version 5.1 and later it is implemented in 64-bit LispWorks as well.
avoid-gc
gc-if-needed
get-gc-parameters
mark-and-sweep
normal-gc
set-gc-parameters
finish-heavy-allocation
without-interrupts
Memory Management in 32-bit LispWorks
LispWorks User Guide and Reference Manual - 20 Sep 2017