VIOMB(4) - Device Drivers Manual #
VIOMB(4) - Device Drivers Manual
NAME #
viomb - VirtIO memory ballooning driver
SYNOPSIS #
viomb* at virtio?
DESCRIPTION #
The viomb driver supports the virtio-compliant memory ballooning device.
Memory ballooning works as follows:
- The host operator requests a guest to return some amount of memory to the host (via, for example, the QEMU monitor balloon command).
- The hypervisor sends the request via the VirtIO memory ballooning device.
- The guest viomb driver requests allocation of that amount of physical memory from the OpenBSD memory management system.
- The viomb device tells the hypervisor the guest physical memory address of the allocated memory via the VirtIO memory ballooning device.
SEE ALSO #
Rusty Russell, IBM Corporation, Virtio PCI Card Specification, http://ozlabs.org/~rusty/virtio-spec/.
HISTORY #
The viomb device driver first appeared in OpenBSD 5.3.
OpenBSD 7.5 - January 16, 2013