Build with jemalloc

[Michael Stahl]

hello Takatsugu,

On 30/08/13 07:12, NOKUBI Takatsugu wrote:
> Does anyone tried to build LibreOffice with jemallc?
> 
> I tried to use LibreOffice on Windows environment, and it required
> too much memory rather than Microsoft Office.
> 
> So I tryied to inspect memory usage with Microsoft Performance Analyzer.
> http://msdn.microsoft.com/en-us/library/windows/desktop/hh448170.aspx
> 
> I can find many malloc/free and new/delete pair, so I suspect
> possibility of heap memory fragmantation.

it is quite possible that there could be issues with the memory
allocator, because LibreOffice is a very demanding application.

although as far as i vaguely remember the really "bad" system memory
allocators are in Windows XP and earlier; the Vista and newer allocators
are said to be much better.

and i would suspect if LibreOffice requires more memory than MS Office
it is most likely not because of the memory allocator but because of
sub-optimal data structures in the application cores (plus some constant
overhead because LibreOffice is portable and thus needs more platform
abstraction layers).

> Then I tried to build with jemalloc, a famous memory allocator.
> 
> I modified desktop/Executable_soffice_bin.mk like the following:
> $(eval $(call gb_Executable_add_ldflags,soffice_bin,\
>     /STACK:10000000 \
>         /NODEFAULTLIB:msvcrt /NODEFAULTLIB:libcmt \
>         'c:\cygwin\libo\jemalloc\jemalloc_s.lib' \
>         'c:\cygwin\libo\jemalloc\libgcc.a' \
>         'C:\Program Files\Microsoft Visual Studio 11.0\VC\lib\msvcrt.lib' \
>         'C:\Program Files\Microsoft Visual Studio 11.0\VC\lib\libcmt.lib' \
> 
> ))
> 
> (it’s a dirty hack)
> 
> So gbuild invoked the following command (a little bit long):
> 
> S=C:/cygwin/libo && O=C:/cygwin/opt/lo/build2/solver/wntmsci14.pro && W=C:/cygwin/opt/lo/build2/workdir/wntmsci14.pro &&  
> mkdir -p $W/LinkTarget/Executable/ && 
> rm -f $W/LinkTarget/Executable/soffice_bin.exe && RESPONSEFILE=C:/cygwin/tmp/gbuild.ThJJlZ &&  
> unset INCLUDE &&  
> link   -release -opt:noref -incremental:no -debug -nxcompat -dynamicbase -manifest  -SUBSYSTEM:WINDOWS,5.01    -LIBPATH:$O/lib -LIBPATH:C:/PROGRA~1/Java/JDK17~1.0_2/lib -LIBPATH:C:/PROGRA~1/MICROS~1.0/VC/lib -LIBPATH:C:/PROGRA~1/WI3CF2~1/8.0/lib -LIBPATH:C:/PROGRA~1/WI3CF2~1/8.0/lib/win8/um/x86 -LIBPATH:C:/PROGRA~1/MICROS~1.NET/SDK/v2.0//lib -LIBPATH:C:/PROGRA~1/MI5E29~1/lib/x86    /STACK:10000000 
> /NODEFAULTLIB:msvcrt
>  /NODEFAULTLIB:libcmt 
> 'c:\cygwin\libo\jemalloc\jemalloc_s.lib' 'c:\cygwin\libo\jemalloc\libgcc.a' 
> 'C:\Program Files\Microsoft Visual Studio 11.0\VC\lib\msvcrt.lib' 
> 'C:\Program Files\Microsoft Visual Studio 11.0\VC\lib\libcmt.lib'  
> @${RESPONSEFILE} isal.lib isofficeapp.lib iuwinapi.lib ooopathutils.lib 
> winextendloaderenv.lib  advapi32.lib  user32.lib -out:$W/LinkTarget/Executable/soffice_bin.exe; RC=$?; rm ${RESPONSEFILE}   && 
> if [ -f $W/LinkTarget/Executable/soffice_bin.exe.manifest ]; then mt.exe  -nologo -manifest $W/LinkTarget/Executable/soffice_bin.exe.manifest
>  outputresource:$W/LinkTarget/Executable/soffice_bin.exe\;1 &&
>  touch -r $W/LinkTarget/Executable/soffice_bin.exe
>  W/LinkTarget/Executable/soffice_bin.exe.manifest; fi &&
>  if [ -f $S/solenv/inc/DeclareDPIAware.manifest ]; then 
> mt.exe  -nologo -manifest $S/solenv/inc/DeclareDPIAware.manifest -updateresource:$W/LinkTarget/Executable/soffice_bin.exe\;1 ;
>  fi  ; exit $RC
> 
> I thknk it seems fine, but the output binary hadn’t have static jemalloc code.

i don't know why this does not work for the specific case of
soffice.bin, because i don't know what symbols are in the extra
libraries you link.  perhaps there are different calling conventions in
the jemalloc library and the soffice.bin objects or something like that,
so it still picks up the allocator symbols from msvcrt.lib.

> Does anyone tried same thing? 
> Or how can I build LibreOffice with jemalloc static library?

but in any case just adapting soffice.bin is not sufficient on Windows,
because dynamic libraries on Windows work differently than on ELF based
platforms.  with ELF you can add global symbols for malloc, operator new
etc. to the executable and they will be visible to every DSO in the
process, effectively overriding the same symbols from libc.so.
(incidentally this is how we replace the system memory allocator on
Linux with the one in our sal library.)

this does not work on Windows because DLLs do not have a global symbol
namespace, their namespace is local to each DLL.  and every DLL knows
not only the name of an imported symbol, but also which other DLL it is
imported from.  so i think what you would need to do to replace the
memory allocator on Windows is to link _every_ DLL and executable
against your custom allocator.

(there is already the --with-alloc=jemalloc configure option but it will
work only on ELF platforms due to this reason.)

oh, and for quite a lot of classes in the code base a custom memory
allocator is used anyway due to overloading operator new for the
particular class, see include/tools/mempool.hxx and the underlying
rtl_cache API in include/rtl/alloc.h.  this implements a SLAB like
allocator which is used for the most-used classes and should be quite
efficient and reduce the fragmentation considerably.

as far as i know OOo has never replaced the general system memory
allocator on Windows, but i don't know why that is.  perhaps with the
rtl_cache being used for many things there is not much of a benefit to it.

regards,
 michael