This configuration variable turns on the caching of data blocks for file
reads. By default, Vision 4 does not cache data blocks in its internal cache (all
V_BUFFERS are allocated only to index blocks). This is required for the
asynchronous reads feature (V_LOCK_METHOD=2) to work properly (each data record needs
to be read/written in a single system call). The default setting of this
configuration variable is "0" (off).
If you are not using the asynchronous reads feature at all, you may turn on the caching of data blocks by setting the
V_NO_ASYNC_CACHE_DATA configuration variable to "1". This may improve READ performance.