/***************************************************************************
 *                                                                         *
 * Due to the way Windows API functions report memory metrics,             *
 * it is impossible to accurately retrieve swap (virtual memory)           *
 * sizes as Windows reports the total commit memory which is physical      *
 * memory plus swap file sizes. The only resolution that could be applied  *
 * was calculatively deducting the swap sizes knowing the page and         *
 * physical memory sizes.                                                  *
 *                                                                         *
 * While developing this solution, it was found that sometimes (in         *
 * virtualized environments or when page file is disabled) the calculated  *
 * swap values are outside of possible bounds. For example, the available  *
 * swap size may appear to be larger than the total swap memory size of    *
 * the system, or even the calculated swap sizes may result in negative    *
 * values (in system with disabled page file).                             *
 *                                                                         *
 * Taking these fallacious conditions into account, these calculations     *
 * guarantee that the available swap size is never larger than the total   *
 * available (if it is reported as such, it is lowered to the total        *
 * as there is a higher probability of that number staying consistent      *
 * than the other way around). In case of swap size calculations resulting *
 * in negative values, the corresponding values are set to 0.              *
 *                                                                         *
 * As the result the returned values might not be exactly accurate         *
 * depending on the system and environment, but they ought to be close     *
 * enough.                                                                 *
 *                                                                         *
 * NB: The reason why GlobalMemoryStatus[Ex] are used is their             *
 * availability on Windows 2000 and later, as opposed to other functions   *
 * of a similar nature (like GetPerformanceInfo) that are not supported    *
 * on some versions of Windows.                                            *
 *                                                                         *
 ***************************************************************************/

ページングファイル：2,432MB       <- paging file

物理メモリの合計：16,376 MB       <- physical memory
利用できる物理メモリ：14,947 MB   <- available physical memory
仮想メモリ：最大サイズ：18,808 MB <- virtual memory max
仮想メモリ：利用可能：13,195 MB   <- available virtual memory
仮想メモリ：使用中：5,613 MB      <- used virtual memory

c:\Program Files\Zabbix Agent>zabbix_agentd -t system.swap.size[,free]
system.swap.size[,free]                       [u|0]

c:\Program Files\Zabbix Agent>zabbix_agentd -t system.swap.size[,free]
system.swap.size[,free]                       [u|451350528]

> memstat
Used memory statistics:
        GlobalMemoryStatusEx():
                commit: 4340684 / 5595348
                phys  : 2710880 / 4076980
                swap  : 1629804 / 1518368 (107.34%)
        GetPerformanceInfo():
                commit:  146380 / 1401044
                phys  : 2710884 / 4076980
                cache : 1049316
                swap  : 1629800 / 1518368 (107.34%)
        QueryPerformanceCounter():
                swap bytes: 3201122304
                swap %    : 9.77%

> zabbix_agentd -t system.swap.size[,free]
system.swap.size[,free]                       [u|0]

> systeminfo | find "Memory"
Total Physical Memory:     3,981 MB
Available Physical Memory: 1,328 MB
Virtual Memory: Max Size:  5,464 MB
Virtual Memory: Available: 1,222 MB
Virtual Memory: In Use:    4,242 MB