VCC FLAGS

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VCC_FLAGS is a static system parameter that enables and disables file system data caching on Alpha systems. If caching is enabled, VCC_ FLAGS controls which file system data cache is loaded during system startup.

Values

Value Description
0 Disables file system data caching on the local node and throughout the OpenVMS Cluster. In an OpenVMS Cluster, if caching is disabled on any node, none of the other nodes can use the extended file cache or the virtual I/O cache. They can't cache any file data until that node either leaves the cluster or reboots with VCC_FLAGS set to a nonzero value.
1 Enables file system data caching and selects the Virtual I/O Cache. This is the default for VAX systems.
2 Enables file system data caching and selects the extended file cache. This is the default for Alpha systems.

Note that on Integrity servers, the volume caching product ([SYS$LDR]SYS$VCC.EXE) is not available. XFC caching is the default caching mechanism. Setting the VCC_FLAGS parameter to 1 is equivalent to not loading caching at all or to setting VCC_FLAGS to 0.

VCC_FLAGS is an AUTOGEN parameter.