:original_name: mrs_01_1046.html

.. _mrs_01_1046:

Storm Common Parameters
=======================

This section applies to MRS 3.\ *x* or later.

Navigation Path
---------------

For details about how to set parameters, see :ref:`Modifying Cluster Service Configuration Parameters <mrs_01_2125>`.

Parameter Description
---------------------

.. table:: **Table 1** Parameter description

    
   | Parameter              | Description                                                                                                                                                                                                                                                                                                                                             | Default Value                                                                                                                                                                                                                                                      |
    
   | supervisor.slots.ports | Specifies the list of ports that can run workers on the supervisor. Each worker occupies a port, and each port runs only one worker. This parameter is used to set the number of workers that can run on each server. Ports range from 1024 to 65535, and ports are separated by commas (,).                                                            | 6700,6701,6702,6703                                                                                                                                                                                                                                                |
    
   | WORKER_GC_OPTS         | Specifies the JVM option used for supervisor to start worker. It is recommended that you set this parameter based on memory usage of a service. For simple service processing, the recommended value is **-Xmx1G**. If window cache is used, the value of this parameter is calculated based on the following formula: Size of each record x Period x 2 | -Xms1G -Xmx1G -XX:+UseG1GC -XX:+PrintGCDetails -Xloggc:artifacts/gc.log -XX:+PrintGCDateStamps -XX:+PrintGCTimeStamps -XX:+UseGCLogFileRotation -XX:NumberOfGCLogFiles=10 -XX:GCLogFileSize=1M -XX:+HeapDumpOnOutOfMemoryError -XX:HeapDumpPath=artifacts/heapdump |
    
   | default.schedule.mode  | Specifies the default scheduling mode of the scheduler. Options are as follows:                                                                                                                                                                                                                                                                         | AVERAGE                                                                                                                                                                                                                                                            |
   |                        |                                                                                                                                                                                                                                                                                                                                                         |                                                                                                                                                                                                                                                                    |
   |                        | -  **AVERAGE**: indicates that the scheduling mechanism that uses the number of idle slots as the priority is used.                                                                                                                                                                                                                                     |                                                                                                                                                                                                                                                                    |
   |                        | -  **RATE**: indicates that the scheduling mechanism that uses the rate of idle slots as the priority is used.                                                                                                                                                                                                                                          |                                                                                                                                                                                                                                                                    |
    
   | nimbus.thrift.threads  | Set the maximum number of connection threads when the active Nimbus externally provides services. If the Storm cluster is large and the number of Supervisor instances is large, increase connection threads.                                                                                                                                           | 512                                                                                                                                                                                                                                                                |
    
