Space Locking

To acquire lock in ActiveSpaces, a distributed object MDMLOCKSPACE is defined in Configurator. When TIBCO MDM server starts, the MDMLOCKSPACE is created in ActiveSpaces.

For multiple seeder cache node, it is recommended to replicate MDMCLOCKSPACE. Refer to the following sample:

<Cache>
<Name>MDMLOCKSPACE</Name>
<Description>This space maintains MDM locks</Description>
<Type>distributed</Type>
<ReplicationCount>0</ReplicationCount>
<SingleByteObjectSize>548</SingleByteObjectSize>
<MultiByteObjectSize>818</MultiByteObjectSize>
</Cache>

The MDMLOCKSPACE contains following fields:

MDMLOCKSPACE Fields
Fields ActiveSpaces Data Type Description 
z_id
 String Refers to the cache key. 
THREADID
 Long Refers to the thread ID that acquires the lock. 
THREADNAME
 String Refers to the thread name that acquires the lock. 
DATETIME
 Datetime Indicates the date and time when an entry is locked. You can use the date and time to identify the age of lock. The date and time is stored in the GMT format. 
NODEID
 String Indicates the node ID. Using the combination of NODEID and THREADID, you can identify which node and thread acquired or released the lock.
Note: The MDMLOCKSPACE is an important space that contains the ActiveSpaces lock information. Therefore, it is recommended that you must replicate this space. For MDMLOCKSPACE, if you do not specify <ReplicationCount> as greater than zero, the following warning message is displayed in elink.log:
***** Replication count is not set for MDMLOCKSPACE ********