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| <h5 class="subsubsection">3.2.2.11 Statistics for Memory Allocation with <code>malloc</code></h5> |
| |
| <p><a name="index-allocation-statistics-292"></a>You can get information about dynamic memory allocation by calling the |
| <code>mallinfo</code> function. This function and its associated data type |
| are declared in <samp><span class="file">malloc.h</span></samp>; they are an extension of the standard |
| SVID/XPG version. |
| <a name="index-malloc_002eh-293"></a> |
| <!-- malloc.h --> |
| <!-- GNU --> |
| |
| <div class="defun"> |
| — Data Type: <b>struct mallinfo</b><var><a name="index-struct-mallinfo-294"></a></var><br> |
| <blockquote><p>This structure type is used to return information about the dynamic |
| memory allocator. It contains the following members: |
| |
| <dl> |
| <dt><code>int arena</code><dd>This is the total size of memory allocated with <code>sbrk</code> by |
| <code>malloc</code>, in bytes. |
| |
| <br><dt><code>int ordblks</code><dd>This is the number of chunks not in use. (The memory allocator |
| internally gets chunks of memory from the operating system, and then |
| carves them up to satisfy individual <code>malloc</code> requests; see |
| <a href="Efficiency-and-Malloc.html#Efficiency-and-Malloc">Efficiency and Malloc</a>.) |
| |
| <br><dt><code>int smblks</code><dd>This field is unused. |
| |
| <br><dt><code>int hblks</code><dd>This is the total number of chunks allocated with <code>mmap</code>. |
| |
| <br><dt><code>int hblkhd</code><dd>This is the total size of memory allocated with <code>mmap</code>, in bytes. |
| |
| <br><dt><code>int usmblks</code><dd>This field is unused. |
| |
| <br><dt><code>int fsmblks</code><dd>This field is unused. |
| |
| <br><dt><code>int uordblks</code><dd>This is the total size of memory occupied by chunks handed out by |
| <code>malloc</code>. |
| |
| <br><dt><code>int fordblks</code><dd>This is the total size of memory occupied by free (not in use) chunks. |
| |
| <br><dt><code>int keepcost</code><dd>This is the size of the top-most releasable chunk that normally |
| borders the end of the heap (i.e., the high end of the virtual address |
| space's data segment). |
| |
| </dl> |
| </p></blockquote></div> |
| |
| <!-- malloc.h --> |
| <!-- SVID --> |
| <div class="defun"> |
| — Function: struct mallinfo <b>mallinfo</b> (<var>void</var>)<var><a name="index-mallinfo-295"></a></var><br> |
| <blockquote><p>This function returns information about the current dynamic memory usage |
| in a structure of type <code>struct mallinfo</code>. |
| </p></blockquote></div> |
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