Thin provisioning needs communication to function, and zero page reclaim is only the array side of the story. WRITE_SAME helps reduce I/O load, but the server needs to use it. Wouldn't it be nice if the operating system, file system, or volume manager would use these commands to help recover capacity? We need a bridge. We need to cross the gulf between the storage array … [Read more...] about The Bridge: Veritas Thin (Provisioning) API
One of the sticky wickets that holds back thin provisioning is the need to communicate when capacity is no longer needed. Enterprise storage arrays can reclaim zeroed pages, but writing all those zeros can really fill up an I/O queue. This is where WRITE_SAME comes into the picture. This is a really terrible name. It's all-capital letters and has an underscore in the … [Read more...] about What is WRITE_SAME? Green Eggs and Ham!