This is possibly the most exciting new storage feature in the vSphere 5.1 release. Space Efficient Sparse Virtual Disks (or SE Sparse Disks for short) were designed to alleviate two issues. Let’s describe these issues first of all. Problem Statement #1 – Let’s take a Guest OS running on a linked clone (View desktop if you will), and this Guest OS issues a 4KB write. vmfsSparse disk (which is the format used by traditional linked clones) has a block allocation unit size of 512 bytes. In other words, this Guest OS is backed by 512 byte blocks. Depending on the…
Welcome to the first in a series of posts related to new storage enhancements in vSphere 5.1. The first of these posts will concentrate on VMFS. There are two major enhancements to VMFS-5 in the vSphere 5.1 release. VMFS File Sharing Limits Increase Prior to vSphere 5.1, the maximum number of ESXi hosts which could share a read-only file on a VMFS filesystem was 8. This was a limiting factor for those products and features which used linked clones. Linked Clones are simply “read/write” snapshots of a “master or parent” desktop image. In particular, it was a limitation for vCloud…