You can use FlexShare to give Data ONTAP a hint about how to manage the buffer cache for that volume.
This value tells Data ONTAP to wait as long as possible before reusing the cache buffers. This value can improve performance for a volume that is accessed frequently with a high incidence of multiple accesses to the same cache buffers.
This value tells Data ONTAP to make buffers from this volume available for reuse quickly. You can use this value for volumes that are written but rarely read. Examples of such volumes include database log volumes or volumes for which the data set is so large that keeping the cache buffers will probably not increase the hit rate.
This value tells Data ONTAP to use the default system cache buffer policy for this volume.