Procedure
1 |
Either select the Storage Subsystem >> Change Cache Settings pull-down menu option or use the right mouse button to select the storage subsystem in the Logical View. Then, select Change Cache Settings from the pop-up menu. Result: The Change Cache Settings dialog is displayed. |
2 |
Select the percentage of unwritten data in the cache that will trigger a cache flush, in the Start Value spinner box. Note: A percentage that is too low increases the chance that data needed for a host read will not be in the cache. It also increases the number of disk writes necessary to maintain the cache level, increasing system overhead and decreasing performance. |
3 |
Select the percentage of unwritten data in the cache that will stop a cache flush in progress, in the Stop Value spinner box. Note: The lower the specified percentage, the higher the chance that data for a host read would require a disk read rather than be present in the cache. |
4 |
Select a cache block size that is appropriate for your applications from the Cache block size: drop-down list. Available choices include 4 KB (a good choice for file system or database application use) and 16 KB (a good choice for applications that generate sequential I/O, such as multimedia). |
5 |
Select OK. Result: The storage subsystem controller cache settings are updated. |
Specifying Logical Drive Properties