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— Data type: **vm_statistics_data_t**

This structure is returned in

vm_statsby the`vm_statistics`

function and provides virtual memory statistics for the system. It has the following members:

`long pagesize`

- The page size in bytes.
`long free_count`

- The number of free pages.
`long active_count`

- The umber of active pages.
`long inactive_count`

- The number of inactive pages.
`long wire_count`

- The number of pages wired down.
`long zero_fill_count`

- The number of zero filled pages.
`long reactivations`

- The number of reactivated pages.
`long pageins`

- The number of pageins.
`long pageouts`

- The number of pageouts.
`long faults`

- The number of faults.
`long cow_faults`

- The number of copy-on-writes.
`long lookups`

- The number of object cache lookups.
`long hits`

- The number of object cache hits.

— Function: kern_return_t **vm_statistics** (`vm_task_t target_task, vm_statistics_data_t *vm_stats`)

The function

`vm_statistics`

returns the statistics about the kernel's use of virtual memory since the kernel was booted.`pagesize`

can also be found as a global variable`vm_page_size`

which is set at task initialization and remains constant for the life of the task.