:doc:`Kinesis <../../kinesis>` / Client / update_shard_count

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update_shard_count
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.. py:method:: Kinesis.Client.update_shard_count(**kwargs)

  

  Updates the shard count of the specified stream to the specified number of shards. This API is only supported for the data streams with the provisioned capacity mode.

   

  .. note::

    

    When invoking this API, you must use either the ``StreamARN`` or the ``StreamName`` parameter, or both. It is recommended that you use the ``StreamARN`` input parameter when you invoke this API.

    

   

  Updating the shard count is an asynchronous operation. Upon receiving the request, Kinesis Data Streams returns immediately and sets the status of the stream to ``UPDATING``. After the update is complete, Kinesis Data Streams sets the status of the stream back to ``ACTIVE``. Depending on the size of the stream, the scaling action could take a few minutes to complete. You can continue to read and write data to your stream while its status is ``UPDATING``.

   

  To update the shard count, Kinesis Data Streams performs splits or merges on individual shards. This can cause short-lived shards to be created, in addition to the final shards. These short-lived shards count towards your total shard limit for your account in the Region.

   

  When using this operation, we recommend that you specify a target shard count that is a multiple of 25% (25%, 50%, 75%, 100%). You can specify any target value within your shard limit. However, if you specify a target that isn't a multiple of 25%, the scaling action might take longer to complete.

   

  This operation has the following default limits. By default, you cannot do the following:

   

  
  * Scale more than ten times per rolling 24-hour period per stream
   
  * Scale up to more than double your current shard count for a stream
   
  * Scale down below half your current shard count for a stream
   
  * Scale up to more than 10000 shards in a stream
   
  * Scale a stream with more than 10000 shards down unless the result is less than 10000 shards
   
  * Scale up to more than the shard limit for your account
   
  * Make over 10 TPS. TPS over 10 will trigger the LimitExceededException
  

   

  For the default limits for an Amazon Web Services account, see `Streams Limits <https://docs.aws.amazon.com/kinesis/latest/dev/service-sizes-and-limits.html>`__ in the *Amazon Kinesis Data Streams Developer Guide*. To request an increase in the call rate limit, the shard limit for this API, or your overall shard limit, use the `limits form <https://console.aws.amazon.com/support/v1#/case/create?issueType=service-limit-increase&limitType=service-code-kinesis>`__.

  

  See also: `AWS API Documentation <https://docs.aws.amazon.com/goto/WebAPI/kinesis-2013-12-02/UpdateShardCount>`_  


  **Request Syntax**
  ::

    response = client.update_shard_count(
        StreamName='string',
        TargetShardCount=123,
        ScalingType='UNIFORM_SCALING',
        StreamARN='string',
        StreamId='string'
    )
    
  :type StreamName: string
  :param StreamName: 

    The name of the stream.

    

  
  :type TargetShardCount: integer
  :param TargetShardCount: **[REQUIRED]** 

    The new number of shards. This value has the following default limits. By default, you cannot do the following:

     

    
    * Set this value to more than double your current shard count for a stream.
     
    * Set this value below half your current shard count for a stream.
     
    * Set this value to more than 10000 shards in a stream (the default limit for shard count per stream is 10000 per account per region), unless you request a limit increase.
     
    * Scale a stream with more than 10000 shards down unless you set this value to less than 10000 shards.
    

    

  
  :type ScalingType: string
  :param ScalingType: **[REQUIRED]** 

    The scaling type. Uniform scaling creates shards of equal size.

    

  
  :type StreamARN: string
  :param StreamARN: 

    The ARN of the stream.

    

  
  :type StreamId: string
  :param StreamId: 

    Not Implemented. Reserved for future use.

    

  
  
  :rtype: dict
  :returns: 
    
    **Response Syntax**

    
    ::

      {
          'StreamName': 'string',
          'CurrentShardCount': 123,
          'TargetShardCount': 123,
          'StreamARN': 'string'
      }
      
    **Response Structure**

    

    - *(dict) --* 
      

      - **StreamName** *(string) --* 

        The name of the stream.

        
      

      - **CurrentShardCount** *(integer) --* 

        The current number of shards.

        
      

      - **TargetShardCount** *(integer) --* 

        The updated number of shards.

        
      

      - **StreamARN** *(string) --* 

        The ARN of the stream.

        
  
  **Exceptions**
  
  *   :py:class:`Kinesis.Client.exceptions.InvalidArgumentException`

  
  *   :py:class:`Kinesis.Client.exceptions.LimitExceededException`

  
  *   :py:class:`Kinesis.Client.exceptions.ResourceInUseException`

  
  *   :py:class:`Kinesis.Client.exceptions.ResourceNotFoundException`

  
  *   :py:class:`Kinesis.Client.exceptions.ValidationException`

  
  *   :py:class:`Kinesis.Client.exceptions.AccessDeniedException`

  