If your storage system consistently provides the performance required for your environment, then you do not need FlexShare. If, however, your storage system sometimes does not deliver sufficient performance to some of its users, you can use FlexShare to increase your control over storage system resources to ensure that those resources are being used most effectively for your environment.
For example, you have a mission-critical database on the same storage system as user home directories. You can use FlexShare to ensure that database accesses are assigned a higher priority than accesses to home directories.
You can use FlexShare to ensure that client accesses are assigned a higher priority than system operations.
For example, if you have a database log volume that does not need to be cached after writing, or a heavily accessed volume that should remain cached as much as possible, you can use the cache buffer policy hint to help Data ONTAP determine how to manage the cache buffers for those volumes.
FlexShare enables you to construct a priority policy that helps Data ONTAP manage system resources optimally for your application environment. FlexShare does not provide any performance guarantees.
Use FlexShare with storage systems that have hard disk drives (HDDs) only. FlexShare is not designed for use with storage systems that have solid-state drives (SSDs). Enabling FlexShare on a storage system that has SSDs can result in decreased throughput to SSD-based volumes.