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< FWN‎ | Beats

Revision as of 22:03, 8 November 2009 by Dale (talk | contribs) (starting next ed)


In this section, we cover discussion of Fedora virtualization technologies on the @fedora-virt and @libvirt-list lists.

Contributing Writer: Dale Bewley

Fedora Virtualization List

This section contains the discussion happening on the fedora-virt list.


Andrés García asked[1]


[3] [4]

Libvirt List

This section contains the discussion happening on the libvir-list.

Node device enumeration with udev

Dave Allan posted[1] "a fully functional version of the node device udev[2] based backend, incorporating all the feedback from earlier revisions." "...I have also included a patch removing the DevKit backend."

Also see FWN#146 "Host Device Enumeration API"[3] for some coverage of the host device enumeration API.

Rewrite of QEMU monitor handling

Daniel Berrange posted[1] a "patch series [which] rewrites the QEMU monitor handling almost completely.

The key theme here is to move from a totally synchronous way of interacting with the monitor, to a totally asynchronous way. This allows " Package-x-generic-16.pnglibvirt " to handle receipt & dispatch of asychronous events from QEMU. For example a notification of a disk-full error, or VM state change. In the process of doing this re-factoring I have also dropped in basic support/infrastructure for the JSON based monitor."

Libvirt QEMU driver thread safety rules

In a characteristically long and detailed post Daniel Berrange laid[1] donw the law on thread safety rules for the Qemu driver[2].

"This document describes how thread safety is ensured throughout the QEMU driver. The criteria for this model are:

  • Objects must never be exclusively locked for any pro-longed time
  • Code which sleeps must be able to time out after suitable period
  • Must be safe against dispatch asynchronous events from monitor"

Also see FWN#155 "Thread Safety for libvirtd Daemon and Drivers"[3]