content_image/725730.jpg content_image/725727.jpg content_image/725728.jpg content_image/725729.jpg content_image/725723.jpg
<img src='content_image/725730.jpg'>

When setting up shared memory segments, a node ID, expressed as an integer, is used to identify uniquely the shared memory segment to use for the communication. There is no default value. If UseShm is enabled, the shared memory key is calculated automatically by NDB . 

• ShmSize 

<img src='content_image/725727.jpg'>

Each SHM connection has a shared memory segment where messages between nodes are placed by the sender and read by the reader. The size of this segment is defined by ShmSize . The default value is 4MB. 

• ShmSpinTime 

<img src='content_image/725728.jpg'>

When receiving, the time to wait before sleeping, in microseconds. 

• SigNum 

<img src='content_image/725729.jpg'>

This parameter was used formerly to override operating system signal numbers; in NDB 8.0, it is no longer used, and any setting for it is ignored. 

Restart types.  Information about the restart types used by the parameter descriptions in this section is shown in the following table: 

<img src='content_image/725723.jpg'>

