HP StorageWorks HSG80 Array Controller V8.7 Maintenance And Service Manual page 180

Glossary
write-through cache
A cache management technique for retaining host write requests in read cache. When the host
requests a write operation, the controller writes data directly to the storage device. This
technique allows the controller to complete some read requests from the cache, greatly
improving the response time to retrieve data. The operation is complete only after the data to
be written is received by the target storage device.
This cache management method may update, invalidate, or delete data from the cache memory
accordingly, to ensure that the cache contains the most current data.
write-through caching
A cache management method used to decrease the subsystem's response time to a read. This
method allows the controller to satisfy the request from the cache memory rather than from the
disk drives.
Glossary–14 HSG80 Array Controller V8.7 Maintenance and Service Guide