VMware releases the fifth version of its flagship virtualization system hypervisor

This August, VMware released the fifth version of its flagship virtualization system hypervisor, vsphere 5. The latest version contains nearly 200 new or enhanced features, including many storage-related content. So what are these new vsphere 5 storage features? What impact will these features have on storage administrators?

File system Improvements

Vsphere's 5 launches a new version of the VMware file system, VMFS-5. It uses a block-based storage LUN. This is an upgrade to previous VMFS-3 that includes improvements to performance and scalability.

VMFS-5 allows you to create up to 64TB of data storage capacity on a single LUN. Under VMFS-3, the number is only 2 TB, and the larger capacity is achieved only by aggregating LUNs. The size of the data storage block is 1 MB, and before Vsphere 5, the user can have multiple block size selections including 1 mb,2 mb,4 MB and 8 MB. Consistent block size enables more efficient use of storage, especially in a streamlined configuration environment. Finally, supporting files smaller than 1 KB also makes storage more efficient.

The performance of VMFS based file systems has been improved, and VAAI earlier versions of ATS have been more widely used, which has achieved finer block-level locking. This change means that ATS can be applied in more places with Vmfs, locking files in a smaller block size. In some ways, the increased size of VMFS data storage requires improved locking performance, and the locking of the data storage layer becomes more efficient as data storage sizes increase.

Storage Distributed Resource Scheduling

Vsphere 5 also features storage distributed resource scheduling (storage DRS), a feature that enables virtual machines to load and capacity balance when data is stored. With Vcenter Server, you can now place multiple data stores into a management cluster, where virtual machines can be moved by the I/O load and capacity.

There are two modes of operation for this function.

Based on the data storage capacity and load capacity of each virtual machine within the current cluster, the initial location determines the optimal storage location for deploying virtual machines. Since then, DRS can provide recommendations for migrating virtual machines to improve I/O response time and capacity.

Storage DRS can report recommended virtual machine migrations or automatically migrate vsphere virtual machines when certain thresholds reach critical points. Storage DRS is performed at the Vcenter server level and requires vmotion licenses.

VMware recommends that all data with similar performance characteristics be stored within a cluster to achieve effective load balancing for all resources.

(Responsible editor: Lu Guang)