xnu-7195.101.1.tar.gz

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<h2>vm_statistics</h2>
<hr>
<p>
<strong>Structure</strong> - Defines statistics for the kernel's use of virtual memory.
<h3>SYNOPSIS</h3>
<pre>
<strong>struct vm_statistics</strong>
<strong>{</strong>
       <strong>integer_t</strong>       <var>free_count</var><strong>;</strong>
       <strong>integer_t</strong>       <var>active_count</var><strong>;</strong>
       <strong>integer_t</strong>       <var>inactive_count</var><strong>;</strong>
       <strong>integer_t</strong>       <var>wire_count</var><strong>;</strong>
       <strong>integer_t</strong>       <var>zero_fill_count</var><strong>;</strong>
       <strong>integer_t</strong>       <var>reactivations</var><strong>;</strong>
       <strong>integer_t</strong>       <var>pageins</var><strong>;</strong>
       <strong>integer_t</strong>       <var>pageouts</var><strong>;</strong>
       <strong>integer_t</strong>       <var>faults</var><strong>;</strong>
       <strong>integer_t</strong>       <var>cow_faults</var><strong>;</strong>
       <strong>integer_t</strong>       <var>lookups</var><strong>;</strong>
       <strong>integer_t</strong>       <var>hits</var><strong>;</strong>
<strong>};</strong>

<strong>typedef struct vm_statistics* vm_statistics_t;</strong>
</pre>
<h3>FIELDS</h3>
<dl>
<dt> <var>free_count</var>
<dd>
The total number of free pages in the system.
<p>
<dt> <var>active_count</var>
<dd>
The total number of pages currently in use and pageable.
<p>
<dt> <var>inactive_count</var>
<dd>
The number of inactive pages.
<p>
<dt> <var>wire_count</var>
<dd>
The number of pages that are wired in memory and cannot be paged 
out.
<p>
<dt> <var>zero_fill_count</var>
<dd>
The number of zero-fill pages.
<p>
<dt> <var>reactivations</var>
<dd>
The number of reactivated pages.
<p>
<dt> <var>pageins</var>
<dd>
The number of requests for pages from a pager (such as the i-node
pager).
<p>
<dt> <var>pageouts</var>
<dd>
The number of pages that have been paged out.
<p>
<dt> <var>faults</var>
<dd>
The number of times the <strong>vm_fault</strong> routine has been called.
<p>
<dt> <var>cow_faults</var>
<dd>
The number of copy-on-write faults.
<p>
<dt> <var>lookups</var>
<dd>
The number of object cache lookups.
<p>
<dt> <var>hits</var>
<dd>
The number of object cache hits.
</dl>
<h3>DESCRIPTION</h3>
<p>
The <strong>vm_statistics</strong> structure defines the statistics
available on the kernel's use of 
virtual memory.  The statistics record virtual memory usage since
the kernel was booted.
<p>
For related information for a specific task, see the <strong>task_basic_info</strong>
structure.
<h3>NOTES</h3>
<p>
This structure is machine word length specific because of the memory sizes
returned.
<h3>RELATED INFORMATION</h3>
<p>
Functions:
<a href="task_info.html"><strong>task_info</strong></a>,
<a href="host_page_size.html"><strong>host_page_size</strong></a>. 
<p>
Data Structures:
<a href="task_basic_info.html"><strong>task_basic_info</strong></a>.