Virtual Disk Types

The following disk types are defined in the virtual disk library:

• VIXDISKLIB_DISK_MONOLITHIC_SPARSE – Growable virtual disk contained in a single virtual disk file. This is the default type for hosted disk, and the only setting in the Virtual Disk API Sample Code sample program.
• VIXDISKLIB_DISK_MONOLITHIC_FLAT – Preallocated virtual disk contained in a single virtual disk file. This takes time to create and occupies a lot of space, but might perform better than sparse.
• VIXDISKLIB_DISK_SPLIT_SPARSE – Growable virtual disk split into 2GB extents (s sequence). These files can to 2GB, then continue growing in a new extent. This type works on older file systems.
• VIXDISKLIB_DISK_SPLIT_FLAT – Preallocated virtual disk split into 2GB extents (f sequence). These files start at 2GB, so they take a while to create, but available space can grow in 2GB increments.
• VIXDISKLIB_DISK_VMFS_FLAT – Preallocated virtual disk compatible with ESX 3 and later. Also known as thick disk. This managed disk type is discussed in Managed Disk and Hosted Disk.
• VIXDISKLIB_DISK_VMFS_SPARSE – Employs a copy-on-write (COW) mechanism to save storage space.
• VIXDISKLIB_DISK_VMFS_THIN – Growable virtual disk that consumes only as much space as needed, compatible with ESX 3 or later, supported by VDDK 1.1 or later, and highly recommended.
• VIXDISKLIB_DISK_STREAM_OPTIMIZED – Monolithic sparse format compressed for streaming. Stream optimized format does not support random reads or writes.