(gc-value name) name: a sym returns any type
Retrieves information about the garbage collector.
name must be one of the following symbols:
ratioreturns the garbage collector's current ratio as a floating-point number.
default-ratioreturn the minimum and default values for
ratio, as a floating-point number.
ghost-bytesreturns the number of bytes in each of the garbage collector's generations, as an integer.