+<tag>@-A<size>@:</tag>
+<nidx>-A<size> RTS option</nidx>
+<nidx>allocation area, size</nidx>
+
+[Default: 256k] Set the allocation area size used by the garbage
+collector. The allocation area (actually generation 0 step 0) is
+fixed and is never resized (unless you use <tt/-H/, below).
+
+Increasing the allocation area size may or may not give better
+performance (a bigger allocation area means worse cache behaviour but
+fewer garbage collections and less promotion).
+
+With only 1 generation (<tt/-G1/) the <tt/-A/ option specifies the
+minimum allocation area, since the actual size of the allocation area
+will be resized according to the amount of data in the heap (see
+<tt/-F/, below).
+
+<tag>@-F<factor>@:</tag>
+<nidx>-F<factor> RTS option</nidx>
+<nidx>heap size, factor</nidx>
+
+[Default: 2] This option controls the amount of memory reserved for
+the older generations (and in the case of a two space collector the
+size of the allocation area) as a factor of the amount of live data.
+For example, if there was 2M of live data in the oldest generation
+when we last collected it, then by default we'll wait until it grows
+to 4M before collecting it again.
+
+The default seems to work well here. If you have plenty of memory, it
+is usually better to use <tt/-H<size>/ than to increase
+<tt/-F<factor>/.
+
+The <tt/-F/ setting will be automatically reduced by the garbage
+collector when the maximum heap size (the <tt/-M<size>/ setting)
+is approaching.
+