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(DOCSP-31707): Backport DOCSP-31484 to v6.0. (#5156)
* (DOCSP-31484): Added -Xmn details to our heap memory tuning pages. * (DOCSP-31484): Incorporated Evelyn's feedback.
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source/includes/extracts-troubleshooting.yaml

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@@ -245,41 +245,54 @@ content: |
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The key values in this line are:
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.. list-table::
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:widths: 40 60
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:widths: 10 40 40
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:header-rows: 1
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:stub-columns: 1
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* - Key
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- Value
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- Default
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* - ``-Xmx``
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- Java Heap Maximum Memory
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- 4,352 :abbr:`MB (Megabytes)` (``4352m``)
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* - ``-Xms``
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- Java Heap Starting Memory
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By default, these values are both set to
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4,352 :abbr:`MB (Megabytes)` (``4352m``).
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- 4,352 :abbr:`MB (Megabytes)` (``4352m``)
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* - ``-Xmn``
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- Java Heap Young Generation Memory
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- 1,500 :abbr:`MB (Megabytes)` (``1500m``)
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.. admonition:: Do not change other Java options
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:class: warning
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Changing any option values other than ``-Xmx`` and
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``-Xms`` could have an unexpected impact on the
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|application|. Do not change other values without
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consulting MongoDB Support.
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3. Change the ``-Xmx`` and ``-Xms`` values to a larger
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value. Both parameters should be set to the same value
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to remove any performance impact from the VM constantly
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reclaiming memory from the heap.
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The value is specified as ``#k|m|g``: a number followed
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by
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Changing any option values other than ``-Xmx``,
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``-Xms``, and ``-Xmn`` could have an unexpected impact
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on the |application|. Do not change other values
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without consulting MongoDB Support.
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3. Change the ``-Xmx``, ``-Xms``, and ``Xmn`` values:
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- Change the ``-Xmx`` and ``-Xms`` values to a larger
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value. You should set both parameters to the same value
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to remove any performance impact from the VM constantly
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reclaiming memory from the heap.
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- Change the ``-Xmn`` value to a quarter of the value
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that you specified for the ``-Xmx`` and ``-Xms`` keys.
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Specify the values as ``#k|m|g``: a number followed
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by:
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- ``k`` (kilobytes),
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- ``m`` (megabytes), or
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- ``g`` (gigabytes)
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.. example::
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To set the Java heap to 10 :abbr:`GB (Gigabytes)`,
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set this value to: ``-Xmx10g -Xms10g``
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To set the Java Heap to 12 :abbr:`GB (Gigabytes)`,
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set the values to: ``-Xmx12g -Xms12g -Xmn3g``.
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- id: windows
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name: Windows Hosts
@@ -347,7 +360,7 @@ content: |
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.. example::
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To set the Java heap to 10 :abbr:`GB (Gigabytes)`,
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To set the Java Heap to 10 :abbr:`GB (Gigabytes)`,
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set this value to: ``-Xmx10g -Xms10g``
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The optimal value for your |onprem| installation depends upon your
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.. important::
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Your Java heap size must not be set to a value greater than the
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Your Java Heap size must not be set to a value greater than the
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amount of physical memory in the |onprem| host or less than the
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default value of ``4352m`` (4,352 :abbr:`MB (Megabytes)`).
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source/reference/troubleshooting/system.txt

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Original file line numberDiff line numberDiff line change
@@ -29,46 +29,54 @@ hosts:
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JAVA_MMS_UI_OPTS="${JAVA_MMS_UI_OPTS} -Xss228k -Xmx4352m -Xms4352m -XX:NewSize=600m -Xmn1500m -XX:ReservedCodeCacheSize=128m -XX:-OmitStackTraceInFastThrow"
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The key values in this line are:
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.. list-table::
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:widths: 40 60
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:stub-columns: 1
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:widths: 10 40 40
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:header-rows: 1
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:stub-columns: 1
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* - Key
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- Value
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- Default
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* - ``-Xmx``
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- Java Heap Maximum Memory
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- 4,352 :abbr:`MB (Megabytes)` (``4352m``)
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* - ``-Xms``
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- Java Heap Starting Memory
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By default, these values are both set to 4,352
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:abbr:`MB (Megabytes)` (``4352m``).
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- 4,352 :abbr:`MB (Megabytes)` (``4352m``)
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* - ``-Xmn``
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- Java Heap Young Generation Memory
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- 1,500 :abbr:`MB (Megabytes)` (``1500m``)
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.. warning:: **Do not change other Java options**
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Changing any option values other than ``-Xmx`` and
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``-Xms`` could have an unexpected impact on the
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|application|. Do not change other values without
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consulting MongoDB Support.
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Changing any option values other than ``-Xmx``,
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``-Xms``, and ``-Xmn`` could have an unexpected impact
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on the |application|. Do not change other values
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without consulting MongoDB Support.
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3. Change the ``-Xmx`` and ``-Xms`` values to a larger
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value. Both parameters should be set to the same value
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to remove any performance impact from the VM constantly
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reclaiming memory from the heap.
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3. Change the ``-Xmx``, ``-Xms``, and ``Xmn`` values:
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- Change the ``-Xmx`` and ``-Xms`` values to a larger
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value. You should set both parameters to the same value
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to remove any performance impact from the VM constantly
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reclaiming memory from the heap.
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The value is specified as ``#k|m|g``: a number followed
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by
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- Change the ``-Xmn`` value to a quarter of the value
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that you specified for the ``-Xmx`` and ``-Xms`` keys.
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Specify the values as ``#k|m|g``: a number followed
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by:
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- ``k`` (kilobytes),
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- ``m`` (megabytes), or
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- ``g`` (gigabytes)
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.. example::
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To set the Java heap to 10 :abbr:`GB (Gigabytes)`,
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set this value to: ``-Xmx10g -Xms10g``
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To set the Java Heap to 12 :abbr:`GB (Gigabytes)`,
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set the values to: ``-Xmx12g -Xms12g -Xmn3g``.
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4. Restart each host running |a-mms| instance on which you made these
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changes.
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.. important::
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Consider the co-located MongoDB processes running on the host and
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do not set your Java heap size to a value greater than the amount of
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do not set your Java Heap size to a value greater than the amount of
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physical memory in the |onprem| host or less than the default value
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of ``4352m`` (4,352 :abbr:`MB (Megabytes)`).
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source/tutorial/monitoring-large-deployments.txt

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@@ -21,10 +21,13 @@ Allocate more RAM to Ops Manager Hosts
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editor.
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2. Find a line where the ``JAVA_MMS_UI_OPTS`` variable defines the
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``-Xms``/``-Xmx`` parameters.
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``-Xms``, ``-Xmx``, and ``-Xmn`` parameters.
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3. Update the values from the default of 4352 MB to 8192 MB or more if
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the hosts have extra free memory.
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3. Update the ``-Xms`` and ``-Xmx`` values from the default of 4352 MB
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to 8192 MB or more if the hosts have extra free memory.
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4. Update the ``-Xmn`` value from the default of 1500 MB to a quarter
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of the value that you specified for ``-Xms`` and ``-Xmx``.
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To learn about how to resolve this error in greater detail, see our
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troubleshooting entry on the

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