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diff --git a/winsup/doc/setup-maxmem.xml b/winsup/doc/setup-maxmem.xml deleted file mode 100644 index 1f5ee31a6..000000000 --- a/winsup/doc/setup-maxmem.xml +++ /dev/null @@ -1,66 +0,0 @@ -<?xml version="1.0" encoding='UTF-8'?> -<!DOCTYPE sect1 PUBLIC "-//OASIS//DTD DocBook V4.5//EN" - "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd"> - -<sect1 id="setup-maxmem"><title>Changing Cygwin's Maximum Memory</title> - -<para> -Cygwin's heap is extensible. However, it does start out at a fixed size -and attempts to extend it may run into memory which has been previously -allocated by Windows. In some cases, this problem can be solved by -changing a field in the file header which is utilized by Cygwin since -version 1.7.10 to keep the initial size of the application heap. If the -field contains 0, which is the default, the application heap defaults to -a size of 384 Megabyte. If the field is set to any other value between 4 and -2048, Cygwin tries to reserve as much Megabytes for the application heap. -The field used for this is the "LoaderFlags" field in the NT-specific -PE header structure (<literal>(IMAGE_NT_HEADER)->OptionalHeader.LoaderFlags</literal>).</para> - -<para> -This value can be changed for any executable by using a more recent version -of the <command>peflags</command> tool from the <literal>rebase</literal> -Cygwin package. Example: - -<screen> -$ peflags --cygwin-heap foo.exe -foo.exe: initial Cygwin heap size: 0 (0x0) MB -$ peflags --cygwin-heap=500 foo.exe -foo.exe: initial Cygwin heap size: 500 (0x1f4) MB -</screen> -</para> - -<para> -Heap memory can be allocated up to the size of the biggest available free -block in the processes virtual memory (VM). By default, the VM per process -is 2 GB for 32 processes. To get more VM for a process, the executable -must have the "large address aware" flag set in the file header. You can -use the aforementioned <command>peflags</command> tool to set this flag. -On 64 bit systems this results in a 4 GB VM for a process started from that -executable. On 32 bit systems you also have to prepare the system to allow -up to 3 GB per process. See the Microsoft article -<ulink url="http://msdn.microsoft.com/en-us/library/bb613473%28VS.85%29.aspx">4-Gigabyte Tuning</ulink> -for more information. -</para> - -<note> -<para> -Older Cygwin releases only supported a global registry setting to -change the initial heap size for all Cygwin processes. This setting is -not used anymore. However, if you're running an older Cygwin release -than 1.7.10, you can add the <literal>DWORD</literal> value -<literal>heap_chunk_in_mb</literal> and set it to the desired memory limit -in decimal MB. You have to stop all Cygwin processes for this setting to -have any effect. It is preferred to do this in Cygwin using the -<command>regtool</command> program included in the Cygwin package. -(see <xref linkend="regtool"></xref>) This example sets the memory limit -to 1024 MB for all Cygwin processes (use HKCU instead of HKLM if you -want to set this only for the current user): - -<screen> -$ regtool -i set /HKLM/Software/Cygwin/heap_chunk_in_mb 1024 -$ regtool -v list /HKLM/Software/Cygwin -</screen> -</para> -</note> - -</sect1> |