Class FreeBsdVirtualMemory

java.lang.Object
oshi.hardware.common.AbstractVirtualMemory
oshi.hardware.common.platform.unix.freebsd.FreeBsdVirtualMemory
All Implemented Interfaces:
VirtualMemory
public abstract class FreeBsdVirtualMemory extends AbstractVirtualMemory

  • Constructor Summary

    Constructors
    Modifier
    Constructor
    Description
    protected
    FreeBsdVirtualMemory(FreeBsdGlobalMemory global)
     

  • Method Summary

    Modifier and Type
    Method
    Description
    long
    getSwapPagesIn()
    Number of pages read from paging/swap file(s) to resolve hard page faults.
    long
    getSwapPagesOut()
    Number of pages written to paging/swap file(s) to free up space in physical memory.
    long
    getSwapTotal()
    The current size of the paging/swap file(s), in bytes.
    long
    getSwapUsed()
    The current memory committed to the paging/swap file(s), in bytes
    long
    getVirtualInUse()
    The memory currently committed by the system, in bytes.
    long
    getVirtualMax()
    The maximum memory that can be committed by the system without extending the paging file(s), in bytes.
    protected abstract long
    queryPagesIn()
    Reads vm.stats.vm.v_swappgsin via the subclass's sysctl mechanism.
    protected abstract long
    queryPagesOut()
    Reads vm.stats.vm.v_swappgsout via the subclass's sysctl mechanism.
    protected abstract long
    querySwapTotal()
    Reads vm.swap_total via the subclass's sysctl mechanism.

    Methods inherited from class AbstractVirtualMemory

    toString
    Modifier and Type
    Method
    Description
    String
    toString()
     

    Methods inherited from class Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

  • Constructor Details

  • Method Details

    • getSwapUsed

      public long getSwapUsed()
      Description copied from interface: VirtualMemory
      The current memory committed to the paging/swap file(s), in bytes
      Returns:
      Swap used in bytes

    • getSwapTotal

      public long getSwapTotal()
      Description copied from interface: VirtualMemory
      The current size of the paging/swap file(s), in bytes. If the paging/swap file can be extended, this is a soft limit.
      Returns:
      Total swap in bytes.

    • getVirtualMax

      public long getVirtualMax()
      Description copied from interface: VirtualMemory
      The maximum memory that can be committed by the system without extending the paging file(s), in bytes. Also called the Commit Limit. If the paging/swap file can be extended, this is a soft limit. This is generally equal to the sum of the sizes of physical memory and paging/swap file(s).

      On Linux, represents the total amount of memory currently available to be allocated on the system based on the overcommit ratio, identified as CommitLimit. This may be higher or lower than the total size of physical and swap memory depending on system configuration.

      Returns:
      Max Virtual Memory in bytes

    • getVirtualInUse

      public long getVirtualInUse()
      Description copied from interface: VirtualMemory
      The memory currently committed by the system, in bytes. Also called the Commit Total. This is generally equal to the sum of the bytes used of physical memory and paging/swap file(s).

      On Windows, committing pages changes this value immediately; however, the physical memory is not charged until the pages are accessed, so this value may exceed the sum of used physical and paging/swap file memory.

      Returns:
      Swap used in bytes

    • getSwapPagesIn

      public long getSwapPagesIn()
      Description copied from interface: VirtualMemory
      Number of pages read from paging/swap file(s) to resolve hard page faults. (Hard page faults occur when a process requires code or data that is not in its working set or elsewhere in physical memory, and must be retrieved from disk.) This property was designed as a primary indicator of the kinds of faults that cause system-wide delays. It includes pages retrieved to satisfy faults in the file system cache (usually requested by applications) and in non-cached mapped memory files.
      Returns:
      Pages swapped in

    • getSwapPagesOut

      public long getSwapPagesOut()
      Description copied from interface: VirtualMemory
      Number of pages written to paging/swap file(s) to free up space in physical memory. Pages are written back to disk only if they are changed in physical memory, so they are likely to hold data, not code. A high rate of pages output might indicate a memory shortage. The operating system writes more pages back to disk to free up space when physical memory is in short supply.
      Returns:
      Pages swapped out

    • querySwapTotal

      protected abstract long querySwapTotal()
      Reads vm.swap_total via the subclass's sysctl mechanism.
      Returns:
      the total swap size in bytes

    • queryPagesIn

      protected abstract long queryPagesIn()
      Reads vm.stats.vm.v_swappgsin via the subclass's sysctl mechanism.
      Returns:
      the cumulative pages-in count

    • queryPagesOut

      protected abstract long queryPagesOut()
      Reads vm.stats.vm.v_swappgsout via the subclass's sysctl mechanism.
      Returns:
      the cumulative pages-out count