Add sortreallocate documentation to the manual

Author: jodavies

doc/manual/prepro.tex

@@ -1936,6 +1936,22 @@ \section{\#skipextrasymbols}
 incorrect.
 
 %--#] skipextrasymbols : 
+%--#[ sortreallocate :
+
+\section{\#sortreallocate}
+\label{presortreallocate}
+
+\noindent Syntax:
+
+\#sortreallocate\index{\#sortreallocate}
+
+\noindent See also ``On sortreallocate;'' (\ref{substaon}).
+
+\noindent Reallocates the small and large buffer (also on the worker threads)
+at the end of the current module. In some cases this can significantly reduce
+\FORM's memory usage as measured by ``resident set size''.
+
+%--#] sortreallocate : 
 %--#[ switch :
 
 \section{\#switch}

doc/manual/setup.tex

@@ -439,6 +439,14 @@ \chapter{The setup}
 with 1/N times the size of the buffer of the master. This may get made a 
 bit bigger when potential conflicts with MaxTermSize occur.
 
+The (typically) largest buffers (the small and large buffers) may be reallocated
+at the end of a single module (see \#sortreallocate (\ref{presortreallocate})) or
+at the end of each module (see ``On sortreallocate;'' (\ref{substaon})). In some
+cases this can significantly reduce \FORM's memory usage as measured by
+``resident set size''. For programs which consist of a large number of very
+quickly-running modules, this can incur a noticable performance penalty if performed
+every module.
+
 The default settings are
 \begin{center}
 \begin{tabular}{lrrr}

doc/manual/statements.tex

@@ -3836,6 +3836,10 @@ \section{off}
 \rightvitem{13cm}{Takes the writing of the statistics back from shorthand 
 mode to the regular statistics mode in which each statistics messages takes 
 three lines of text and one blank line.}
+
+\leftvitem{3.5cm}{sortreallocate\index{off!sortreallocate}}
+\rightvitem{13cm}{Turns off the reallocation of the small and large buffer
+at the end of each module.}
 
 \leftvitem{3.5cm}{threadloadbalancing\index{off!threadloadbalancing}}
 \rightvitem{13cm}{\vspace{1.5ex}Disables the loadbalancing mechanism of 
@@ -4001,6 +4005,14 @@ \section{on}
 \leftvitem{3.5cm}{shortstats\index{on!shortstats}}
 \rightvitem{13cm}{Same as `On shortstatistics'.}
 
+\leftvitem{3.5cm}{sortreallocate\index{on!sortreallocate}}
+\rightvitem{13cm}{Reallocate the small and large buffer (also on the worker
+threads) at the end of every module. In some cases this can significantly reduce
+\FORM's memory usage as measured by ``resident set size''. For programs which
+consist of a large number of very quickly-running modules, this can incur a
+noticable performance penalty. See also \#sortreallocate (\ref{presortreallocate})
+for a single-module version of this feature.}
+
 \leftvitem{3.5cm}{statistics\index{on!statistics}}
 \rightvitem{13cm}{Turns the writing of runtime statistics on. This is the 
 default. It is possible to change this default with one of the setup