SFCache agent

The SmartIO feature of Veritas InfoScale enables data efficiency on your SSDs through I/O caching. Using SmartIO to improve efficiency, you can optimize the cost per I/O per second (IOPS). SmartIO uses advanced, customizable heuristics to determine what data to cache and how that data gets removed from the cache. The heuristics take advantage of Veritas InfoScale's knowledge of the characteristics of the workload.

SmartIO uses a cache area on the target device or devices. The cache area is the storage space that SmartIO uses to store the cached data and the metadata about the cached data. The type of the cache area determines whether it supports VxFS caching or VxVM caching. To start using SmartIO, you can create a cache area with a single command, while the application is online.

For more information about SmartIO, see Veritas InfoScale SmartIO for Solid State Drives Solutions Guide.

The SFCache agent enables, disables, and monitors cache. In case of a cache fault, the application still runs without any issues on the very same system, but with degraded I/O performance. Considering this, the SFCache agent provides an attribute to control the agent behavior. You can either choose to "IGNORE" or initiate "FAILOVER" in case of cache fault.

The SmartIO feature allows more than one cache area for VxFS and one cache area for VxVM on a single node; all object-level caches are created in these cache areas. An SFCache resource is configured per object (either mount point or volume) for which the SmartIO feature needs to be enabled. For VxFS caching, the SFCache resource depends on the Mount or CFSMount resource. For VxVM caching, the SFCache resource depends on the DiskGroup, Volume, VolumeSet, or CVMVolDg resource.

If the SmartIO feature is not enabled on a node, the SFCache agent will work as a simple FileOnOff agent. The SFCache resource state will be reported as ONLINE/OFFLINE, but caching-related operations will not be performed.