Patent ID: 8219681
Filing Date: 2012-07-10
Classification: G06F,H04L

Abstract:
1. A method for managing allocation of storage resources in a storage network, wherein the storage network includes physical data storage on one or more storage arrays that are in the storage network, and the network is in communication with one or more hosts and the network further includes a storage network management system that includes a storage virtualizer capable of intercepting and virtualizing an IO stream from the one or more hosts and which storage network management system further includes a storage and switch controller in communication with the storage virtualizer for storage network management, and the method comprises the steps of: the storage network management system allocating one or more virtual data storage volumes for use by a host computer; the storage network management system presenting the virtual data storage volumes to the host computer as representative of available physical storage on the one or more storage arrays, but not allocating physical data storage for the virtual data storage volumes, wherein the virtual data storage volumes can include regions that are either allocated to physical storage or are unallocated to physical storage pending an IO write request that would normally transform the unallocated regions to allocated regions; if a write IO goes to an unallocated region of the virtual data storage volumes, the storage network management system determining if the write IO is a predictable write IO; if the write IO is a predictable write IO, the storage network management system suppressing the predictable write IO by discarding the predictable write IO and not writing the predictable write IO to avoid allocation of the unallocated region of the virtual data storage volumes on the physical data storage volumes that would normally have been transformed to an allocated region, and upon a read IO for the discarded predicted write IO, responding to the read with a creation of the predicted write IO by an appropriate deterministic algorithm of the storage network management system, wherein the deterministic algorithm creates the IO data returned in response the read for the predictable write, to reduce what would otherwise be normal transformation of an unallocated region to an allocated region.