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..
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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.
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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.
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Virsto Method (Software Defined Storage)
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The I/O Optimization data service addresses the I/O randomness due to the server Hypervisor.
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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.
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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.
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References
http://virsto.com/products/virsto-overview/http://www.vmware.com/company/news/releases/vmw-virsto-021113.html