14.3.13 createcache (creates a cache)

(1) Description

This subcommand creates a cache.

You can create a maximum of 16 caches, including memory caches, disk caches, and two-way caches.

To Page Top

(2) Rules

• You can execute this subcommand when the cluster's status is AVAILABLE.

• The target of this subcommand is the EADS servers whose cluster participation status is online. This subcommand cannot be executed if the cluster contains any EADS server whose cluster participation status is standby. You can determine the cluster participation status with the eztool status command.

• This subcommand can be executed when the target EADS servers are in the following status:

  • Initialized

  • Closed

• To prevent a full garbage collection (FullGC) from occurring while operations are underway, each EADS server performs FullGC when this subcommand terminates.

• While this subcommand has obtained a lock from an EADS server, the EADS server is not isolated. However, if processing is shut down or the EADS server terminates while the subcommand has the lock, the lock is released, and then the EADS server is isolated.

To Page Top

(3) Format

eztool createcache cache-name

To Page Top

(4) Options and arguments

To Page Top

(5) Return code

The following table lists the return codes that this subcommand returns.

To Page Top

(6) Notes

• If no cache property file has been created, a memory cache is created.

• If the cache type is memory cache or two-way cache, an error results if either of the following conditions, as applicable, is satisfied:

  • Condition when the total data restriction function is enabled

    The value obtained by dividing the size of the area that stores the value part of the eads.java.external.heapsize parameter in the shared properties by the number of redundant copies of data plus the original is less than 1 megabyte.

  • Condition when the total data restriction function is disabled

    The size of the area that stores the value part of the eads.java.external.heapsize parameter in the shared properties is zero.

• When a cache is created, the number of threads created for the cache is 2 (data multiplicity 2 - 1). Note that, as the number of threads increases, the amount of memory used also increases.

• If cache creation processing fails, use one of the following methods to create the cache again:

  • Execute the eztool listcache command to determine if the cache exists. If it does exist, use the eztool deletecache command to delete the cache, and then re-create the cache.

  • If the cache type is disk cache or two-way cache, execute the eztool listecf command to determine if the cache files exist. If they do exist, use the eztool deleteecf command to delete the cache files, and then re-create the cache.

  • Check the parameter values specified in the cache property file. If the parameter values are invalid, correct them, and then re-create the cache.

  • Check the eads.java.external.heapsize parameter value in the shared properties. If the parameter value is invalid, correct it, and then re-create the cache.

To Page Top