How VxVM works with the operating system

VxVM operates as a subsystem between your operating system and your data management systems, such as file systems and database management systems. VxVM is tightly coupled with the operating system. Before a disk or LUN can be brought under VxVM control, the disk must be accessible through the operating system device interface. VxVM is layered on top of the operating system interface services, and is dependent upon how the operating system accesses physical disks.

VxVM is dependent upon the operating system for the following functionality:

VxVM relies on the following constantly-running daemons and kernel threads for its operation:


The VxVM configuration daemon maintains disk and group configurations and communicates configuration changes to the kernel, and modifies configuration information stored on disks.


VxVM I/O kernel threads provide extended I/O operations without blocking calling processes. By default, 16 I/O threads are started at boot time, and at least one I/O thread must continue to run at all times.


The hot-relocation daemon monitors VxVM for events that affect redundancy, and performs hot-relocation to restore redundancy. If thin provision disks are configured in the system, then the storage space of a deleted volume is reclaimed by this daemon as configured by the policy.