Sunday, February 17, 2013

VMware acquired Virsto - Software Defined Storage (SDDC approach)

Introducing the Virsto Storage Hypervisor

VMware is Geared up & taking big leap on "Software Defined Data Center" by acquiring Virsto.
Virsto has developed a new approach for storage in virtualized environments. Virsto delivers purpose-built software defined storage with its VM-centric storage hypervisor, which provides a set of high-performance data services.

Traditional Method to access Storage..

The Hypervisor (applicable to ESX, ESXi and Hyper-V) acts as a multiplexer to the VMs’ I/O, interleaving the I/O of all the VMs on the host.  As a result, the I/O coming from the Hypervisor is mixed up.  This I/O is what is presented to the underlying storage layer.

When this I/O stream hits the storage layer, it looks like random I/O.  Random I/O presents a challenge for traditional storage because with spinning disks, the mechanics of laying down random writes on disk causes rotational latencies and prolongs seek times.  The consequence of this type of I/O is that storage performance, particularly write performance, degrades.

Virsto Method (Software Defined Storage)

The I/O Optimization data service addresses the I/O randomness due to the server Hypervisor.

The Virsto Storage Hypervisor sits on each host and presents a virtual storage appliance (VSA) to the VMs on the host.  The VMs see Virsto as a new storage mount point, which means Virsto is in the I/O path for the VMs.  Virsto offloads the I/O from the Hypervisor in a more efficient manner.

With the I/O Optimization data service, the Virsto Storage Hypervisor will perform a set of actions on the I/O so it is sequentialized and sent to the storage layer in orderly, logical blocks.