the ON/OFF selection ,indicating whether or not a cache will be active on the specified drive. Again, pointing and clicking with the mouse will make the selection. After ON is selected, a cursor will appear in the DISK MAXIMUM CACHE SIZE box at the bottom of the cache section of the screen . Use the keyboard to enter the desired size of the cache. Click on the ON box a second time if you need to change the cache size to a different number. (“Blocks” are the recognized measure of disk storage. One block equals 512 bytes of RAM. A maximum size of 64 blocks is recommended, with a minimum of 8 blocks). In the TOTAL BUFFER POOL SIZE section of the screen you will notice that the amount of memory allocated to caching is updated as

you designate disk cache sizes . Please note that the Total Buffer Pool Size defaults to automatically show the size of the current buffer pool, created via Dynamic Cache Alllocation. When the desired settings have

been made, click on the “OK’ box

to return to the

menu bar.

 

NOTE: The Total Buffer Pool Size is limited to 3.5 megabytes, or 65,535 buffers. During manual cache allocation, the Total Buffer Pool Size equals the sum of all the buffers allocated for all active drives. If this total exceeds 65,535, the display will show only the difference between the total number of buffers allocated and 65,535. In addition, the utility will only allocate this difference as the Total Buffer Pool Size. As a result, if the Total Buffer Pool Size displays fewer buffers than you have allocated, you should begin decreasing the number of buffers on each active drive until the Total Buffer Pool Size displays the sum of the buffers in all active drives.

Dynamic Cache Allocation

This selection will take over all the caching functions of the manual allocation menu for you, dynamically updating the allocations as appropriate for your

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