cacheutil Command--Show or Destroy Buffer Caches
Permission required: System administrator. On VMS, OpenVMS privileges.
The cacheutil utility returns information about shared memory buffer caches installed in the Ingres installation. The utility can show brief or detailed information about existing caches that are no longer in use. It can also destroy shared memory segments used for buffer caches that are no longer in use. Cacheutil does not destroy a buffer cache that is currently in use.
The cacheutil command has the following format:
cacheutil
cacheutil
Displays the cacheutil command prompt, where you can enter any of the following cacheutil commands:
list
Lists the existing shared buffer caches for the installation, including the size of the cache and the number of connected DBMS Servers.
show cache_name
Displays detailed statistics on the specified shared buffer cache.
destroy cache_name
Destroys the shared memory segment associated with the specified cache name.
This is needed on systems where shared segments are allocated in a manner such that they are not automatically released when all DBMS Servers connected to them are brought down. On these systems, if a DBMS with a shared memory cache fails or is brought down in an unsupported manner, the shared memory segment cannot be automatically cleaned up by the recovery system.
In systems where shared segments are automatically released, when the failed server is restarted, it will automatically clean up the old shared segment. In this case cacheutil is not necessary to release the shared memory.
However, if no server will be restarted that specifies the same cache name as the orphaned cache, then the shared segment must be cleaned up through the destroy option of cacheutil.
help
Displays help on the cacheutil utility.
exit
Closes the cacheutil utility.
Last modified date: 08/28/2024