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+ .. warning ::
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+
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+ Be careful when splitting chunks. When you shard a collection that
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+ has existing data, MongoDB automatically creates chunks to evenly
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+ spread the collection. Performing additional splits requires
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+ knowledge of the resulting chunk sizes by numbers of documents and by
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+ size. You do not want splits that cause some chunks to be much larger
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+ than others. This leads to balancing based on count of chunks, not on
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+ their size, which may cause extreme load/data-distribution problems.
Original file line number Diff line number Diff line change @@ -12,20 +12,10 @@ split
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this command makes it possible for administrators to manually
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create splits.
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- In normal operation there is no need to manually split chunks. The
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- :term:`balancer` and other sharding infrastructure will automatically
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- create chunks in the course of normal operations. See
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- :doc:`/core/sharded-cluster-internals` for more information.
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-
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- .. warning::
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-
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- Be careful when splitting chunks. When you shard a collection that
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- has existing data, MongoDB automatically creates chunks to evenly
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- spread the collection. Performing additional splits requires
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- knowledge of the resulting chunk sizes by numbers of documents and by
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- size. You do not want splits that cause some chunks to be much larger
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- than others. This leads to balancing based on count of chunks, not on
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- their size, which may cause extreme load/data-distribution problems.
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+ In most clusters, MongoDB will manage all chunk creation and
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+ distribution operations without manual intervention.
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+
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+ .. include:: /includes/warning-splitting-chunks.rst
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Consider the following example:
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Original file line number Diff line number Diff line change @@ -10,14 +10,6 @@ splitChunk
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:method:`sh.splitFind()` and :method:`sh.splitAt()` functions in the
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:program:`mongo` shell to access this functionality.
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- .. warning::
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-
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- Be careful when splitting chunks. When you shard a collection that
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- has existing data, MongoDB automatically creates chunks to evenly
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- spread the collection. Performing additional splits requires
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- knowledge of the resulting chunk sizes by numbers of documents and by
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- size. You do not want splits that cause some chunks to be much larger
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- than others. This leads to balancing based on count of chunks, not on
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- their size, which may cause extreme load/data-distribution problems.
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+ .. include:: /includes/warning-splitting-chunks.rst
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.. admin-only.
Original file line number Diff line number Diff line change @@ -58,15 +58,7 @@ You may want to split chunks manually if:
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values between ``300`` and ``400``, *but* all values of your shard
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keys are between ``250`` and ``500`` are in a single chunk.
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- .. warning::
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-
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- Be careful when splitting chunks. When you shard a collection that
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- has existing data, MongoDB automatically creates chunks to evenly
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- spread the collection. Performing additional splits requires
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- knowledge of the resulting chunk sizes by numbers of documents and by
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- size. You do not want splits that cause some chunks to be much larger
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- than others. This leads to balancing based on count of chunks, not on
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- their size, which may cause extreme load/data-distribution problems.
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+ .. include:: /includes/warning-splitting-chunks.rst
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Use :method:`sh.status()` to determine the current chunks ranges across
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the cluster.
You can’t perform that action at this time.
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