[project @ 2001-08-13 16:33:43 by simonmar]

Document -c<n> and bring up to date the documentation of -M<size.

diff --git a/ghc/docs/users_guide/runtime_control.sgml b/ghc/docs/users_guide/runtime_control.sgml
index e97a57d..bbf4dc3 100644 (file)
--- a/ghc/docs/users_guide/runtime_control.sgml
+++ b/ghc/docs/users_guide/runtime_control.sgml
@@ -149,6 +149,20 @@
       </varlistentry>
 
       <varlistentry>
+       <term><option>-c</option><replaceable>n</replaceable></term>
+
+       <listitem>
+         <para>&lsqb;Default: 30&rsqb; Automatically enable
+         compacting collection when the live data exceeds
+         <replaceable>n</replaceable>&percnt; of the maximum heap size
+         (see the <option>-M</option> option).  Note that the maximum
+         heap size is unlimited by default, so this option has no
+         effect unless the maximum heap size is set with
+         <option>-M</option><replaceable>size</replaceable>. </para>
+       </listitem>
+      </varlistentry>
+
+      <varlistentry>
        <term><option>-F</option><replaceable>factor</replaceable></Term>
        <listitem>
          <indexterm><primary><option>-F</option></primary><secondary>RTS option</secondary></indexterm>
@@ -269,7 +283,7 @@
        <indexterm><primary><option>-M</option></primary><secondary>RTS option</secondary></indexterm>
        <indexterm><primary>heap size, maximum</primary></indexterm>
        <listitem>
-         <para>&lsqb;Default: 64M&rsqb; Set the maximum heap size to
+         <para>&lsqb;Default: unlimited&rsqb; Set the maximum heap size to
           <replaceable>size</replaceable> bytes.  The heap normally
           grows and shrinks according to the memory requirements of
           the program.  The only reason for having this option is to
@@ -277,6 +291,14 @@
           available swap space, which at the least will result in the
           program being summarily killed by the operating
           system.</para>
+
+         <para>The maximum heap size also affects other garbage
+         collection parameters: when the amount of live data in the
+         heap exceeds a certain fraction of the maximum heap size,
+         compacting collection will be automatically enabled for the
+         oldest generation, and the <option>-F</option> parameter
+         will be reduced in order to avoid exceeding the maximum heap
+         size.</para>
        </listitem>
       </varlistentry>