klish/lubheap/README

/**
\defgroup lubheap "Little Useful Bits Heap" Library
@{
\section Overview
This library can be linked with executables to override the standard memory
management provided by the system libraries. This may provide a 
performance and debugging advantage.

The implementation uses the \ref lub_heap component to control system memory
and hence provides all the features available within that memory manager. 
(including leak detection)

\section VxWorks
Replaces the memPartLib.o, memLib.o and memShow.o found in the
libos.a library archive.

\subsection memlib memLib.o functions
<code>
calloc, cfree, memFindMax, memInit, memLibInit, memOptionsSet, 
memPartFindMax, memPartOptionsSet, memPartRealloc, memalign, realloc, valloc
</code>

\subsection mempartlib memPartLib.o functions
<code>
free, malloc, memAddToPool, memPartAddToPool, memPartAlignedAlloc, 
memPartAlloc, memPartBlockIsValid, memPartCreate, memPartFree, 
memPartInit, memPartLibInit
</code>

\subsection memshow memShow.o functions
<code>
memShow, memPartInfoGet, memParShow
</code>

\section posix POSIX
Replaces the dynamic memory functionality found in the libc.a 
library archive.

This implementation relies on the sbrk() function to provide memory
chunks to feed the standard heap.

\subsection Functions
<code>
calloc, cfree, free, malloc, memalign, realloc, valloc
</code>


\section Performance
Running the unittests with this library provides the following comparisons on
some test machines:

\section x86_64-unknown-linux-gnu
<TABLE>
<TR>
  <TD><B>Native memory management</B> (<code>./test/mallocTest</code>)</TD>
  <TD><B>lubheap memory management</B> (<code>./test/lubMallocTest</code>)</TD>
</TR>
<TR>
<TD>
<PRE>
***    100 in          0 milliseconds
***    200 in          0 milliseconds
***    300 in          0 milliseconds
***    400 in          0 milliseconds
***    500 in          1 milliseconds
***   1000 in          3 milliseconds
***   2000 in          7 milliseconds
***   3000 in         12 milliseconds
***   4000 in         16 milliseconds
***   5000 in         21 milliseconds
***  10000 in         48 milliseconds
***  15000 in         79 milliseconds
***  20000 in        143 milliseconds
***  25000 in        200 milliseconds
***  30000 in        253 milliseconds
***  35000 in        314 milliseconds
***  40000 in        378 milliseconds
***  45000 in        460 milliseconds
***  50000 in        561 milliseconds
***  60000 in        790 milliseconds
***  70000 in       1036 milliseconds
***  80000 in       1320 milliseconds
***  90000 in       1653 milliseconds
*** 100000 in       2037 milliseconds
</PRE>
</TD>
<TD>
<PRE>
***    100 in          0 milliseconds
***    200 in          0 milliseconds
***    300 in          0 milliseconds
***    400 in          1 milliseconds
***    500 in          1 milliseconds
***   1000 in          3 milliseconds
***   2000 in          6 milliseconds
***   3000 in          9 milliseconds
***   4000 in         11 milliseconds
***   5000 in         13 milliseconds
***  10000 in         37 milliseconds
***  15000 in         49 milliseconds
***  20000 in         61 milliseconds
***  25000 in         75 milliseconds
***  30000 in         89 milliseconds
***  35000 in         99 milliseconds
***  40000 in        113 milliseconds
***  45000 in        125 milliseconds
***  50000 in        138 milliseconds
***  60000 in        177 milliseconds
***  70000 in        203 milliseconds
***  80000 in        228 milliseconds
***  90000 in        254 milliseconds
*** 100000 in        277 milliseconds
</PRE>
</TD>
</TR>
</TABLE>

\section i686-pc-linux-gnu
<TABLE>
<TR>
  <TD><B>Native memory management</B> (<code>./test/mallocTest</code>)</TD>
  <TD><B>lubheap memory management</B> (<code>./test/lubMallocTest</code>)</TD>
</TR>
<TR>
<TD>
<PRE>
***    100 in          0 milliseconds
***    200 in          0 milliseconds
***    300 in          0 milliseconds
***    400 in          1 milliseconds
***    500 in          1 milliseconds
***   1000 in          3 milliseconds
***   2000 in          7 milliseconds
***   3000 in         12 milliseconds
***   4000 in         16 milliseconds
***   5000 in         21 milliseconds
***  10000 in         46 milliseconds
***  15000 in         76 milliseconds
***  20000 in        111 milliseconds
***  25000 in        151 milliseconds
***  30000 in        199 milliseconds
***  35000 in        256 milliseconds
***  40000 in        318 milliseconds
***  45000 in        393 milliseconds
***  50000 in        472 milliseconds
***  60000 in        658 milliseconds
***  70000 in        874 milliseconds
***  80000 in       1121 milliseconds
***  90000 in       1411 milliseconds
*** 100000 in       1745 milliseconds
</PRE>
</TD>
<TD>
<PRE>
***    100 in          0 milliseconds
***    200 in          0 milliseconds
***    300 in          1 milliseconds
***    400 in          1 milliseconds
***    500 in          1 milliseconds
***   1000 in          4 milliseconds
***   2000 in          7 milliseconds
***   3000 in         11 milliseconds
***   4000 in         13 milliseconds
***   5000 in         15 milliseconds
***  10000 in         42 milliseconds
***  15000 in         57 milliseconds
***  20000 in         72 milliseconds
***  25000 in         89 milliseconds
***  30000 in        105 milliseconds
***  35000 in        121 milliseconds
***  40000 in        136 milliseconds
***  45000 in        154 milliseconds
***  50000 in        169 milliseconds
***  60000 in        213 milliseconds
***  70000 in        246 milliseconds
***  80000 in        278 milliseconds
***  90000 in        311 milliseconds
*** 100000 in        341 milliseconds
</PRE>
</TD>
</TR>
</TABLE>

\section i686-pc-cygwin
For some reason the native memory management under cygwin is quicker. My suspcion is that there is an overhead in the
<CODE>sbrk()</CODE> call via the cygwin sub-system which slows the lubheap implementation...
<TABLE>
<TR>
  <TD><B>Native memory management</B> (<code>./test/mallocTest</code>)</TD>
  <TD><B>lubheap memory management</B> (<code>./test/lubMallocTest</code>)</TD>
</TR>
<TR>
<TD>
<PRE>
***    100 in          0 milliseconds
***    200 in          0 milliseconds
***    300 in          0 milliseconds
***    400 in          0 milliseconds
***    500 in          0 milliseconds
***   1000 in          0 milliseconds
***   2000 in          0 milliseconds
***   3000 in         16 milliseconds
***   4000 in         15 milliseconds
***   5000 in         16 milliseconds
***  10000 in         31 milliseconds
***  15000 in         47 milliseconds
***  20000 in         63 milliseconds
***  25000 in         93 milliseconds
***  30000 in        125 milliseconds
***  35000 in        204 milliseconds
***  40000 in        203 milliseconds
***  45000 in        218 milliseconds
***  50000 in        266 milliseconds
***  60000 in        328 milliseconds
***  70000 in        360 milliseconds
***  80000 in        406 milliseconds
***  90000 in        500 milliseconds
*** 100000 in        515 milliseconds
</PRE>
</TD>
<TD>
<PRE>
***    100 in          0 milliseconds
***    200 in          0 milliseconds
***    300 in          0 milliseconds
***    400 in          0 milliseconds
***    500 in         15 milliseconds
***   1000 in          0 milliseconds
***   2000 in         16 milliseconds
***   3000 in         31 milliseconds
***   4000 in         31 milliseconds
***   5000 in         47 milliseconds
***  10000 in         94 milliseconds
***  15000 in        156 milliseconds
***  20000 in        188 milliseconds
***  25000 in        250 milliseconds
***  30000 in        281 milliseconds
***  35000 in        375 milliseconds
***  40000 in        375 milliseconds
***  45000 in        453 milliseconds
***  50000 in        484 milliseconds
***  60000 in        625 milliseconds
***  70000 in        672 milliseconds
***  80000 in        813 milliseconds
***  90000 in        875 milliseconds
*** 100000 in        984 milliseconds
</PRE>
</TD>
</TR>
</TABLE>

@}
*/