Archived/Xen Roadmap/4.3

== Proposed timeline ==
We are planning on a 9-month release cycle. Xen 4.2 was released on 17 September 2012. Based on that, below are our estimated dates:
* Feature Freeze: 25 March, 2013
* Code Freezing point: 15 April, 2013
* First RC: 6 May 2013 
* Release: 2 July 2013
The RCs and release will of course depend on stability and bugs, and
will therefore be fairly unpredictable. Each new feature will be
considered on a case-by-case basis; but the general rule will be as
follows:
Last updated 27 June 2013
== Feature list ==
Below is a list of features we're tracking for this release. If you have updates to a tracked feature you are working on, or are working on a feature and wish it to be tracked, please let me know.
NB: Several of the items on this list marked (external). These are not part of the Xen tree, but are directly related to our users' experience (e.g., work in Linux or qemu) or to integration with other important projects (e.g., libvirt indings). Since all of these are part of the Xen community work, and comes from the same pool of labor, it makes sense to track the progress here, even though they won't explicitly be released as part of 4.3.
Meanings of prognoses:
* Excellent: It would be very unlikely for this not to be finished in time.
* Good: Everything is on track, and is likely to make it.
* Fair: A pretty good chance of making it, but not as certain
* Poor: Likely not to make it unless intervention is made
* Not for 4.3: Self-explanatory
=== Completed ===
* Default to QEMU upstream (partial)
 - pci pass-thru (external)
 - enable dirtybit tracking during migration (external)
 - xl cd-{insert,eject} (external)
* openvswitch toostack integration
 To label "tech-preview" unless we get good testing (>10 individuals)
* NUMA scheduler affinity
* Install into /usr/local by default
 owner: Ian Campbell
* Persistent grants for blk (external)
 - Linux
 - qemu
* Allow XSM to override IS_PRIV checks in the hypervisor
* vTPM updates
* Scalability: 16TiB of RAM
* CPUID-based idle (don't rely on ACPI info f/ dom0)
* Serial console improvements
 -EHCI debug port
=== Bugs ===
* qemu-upstream not freeing pirq
 > http://www.gossamer-threads.com/lists/xen/devel/281498
 priority: high, probably not a blocker
 status: patches posted
* AMD: IOMMU accidental clearing
 owner: Jan Beulich, Suravee Suthikulpanit
 status: 
* __update_vcpu_system_time if system_time comes out negative
 status: Not for 4.3
=== Not yet completed ===
* ARM v7 server port (basic)
* ARM v8 server port (basic)
 - Goal: Good Arndale support for 4.3
 - Regressions here will not slip the release, so development is ongoing
=== External projects (Not affected by feature freeze) ===
* xl pci-detach broken for pv guests?
 > http://bugs.xenproject.org/xen/bug/12
 > kernel doesn't know about moving into states 7 and 8
 status: External
* Race in PV shutdown between tool detection and shutdown watch
 > http://www.gossamer-threads.com/lists/xen/devel/282467
 > Nothing to do with ACPI
 status: Probably a bug in Linux xen drivers
* Multi-page blk rings (external)
 - blkback in kernel roger@citrix
 - qemu blkback
 status: Overall blk architecture being discussed
 prognosis: Fair
* Xen EFI feature: Xen can boot from grub.efi
 owner: Daniel Kiper
 status: Just begun
 prognosis: Fair
* libvirt/libxl integration (external)
 - Update libvirt to 4.2
 status: Patch accepted
 - Migration
 owner: cyliu@suse (?)
 status: first draft implemented, not yet submitted
 prognosis: ?
 - Itemize other things that need work
 To begin with, we need someone to go and make some lists:
 - Features available in libvirt/KVM not available in libvirt/libxl
 See http://libvirt.org/hvsupport.html
 - Features available in xl/Xen but not available in libvirt/Xen
=== For future releases ===
* xl does not handle migrate interruption gracefully
 > If you start a localhost migrate, and press "Ctrl-C" in the middle,
 > you get two hung domains
 status: Probably not for 4.3
* libxl / xl does not handle failure of remote qemu gracefully
 > Easiest way to reproduce: 
 > - set "vncunused=0" and do a local migrate
 > - The "remote" qemu will fail because the vnc port is in use
 > The failure isn't the problem, but everything being stuck afterwards is
 status: Probably not for 4.3
* qxl
 > http://bugs.xenproject.org/xen/bug/11http://bugs.xenproject.org/xen/bug/11
 - Uninitialized struct element in qemu
 - Revert 5479961 to re-enable qxl in xl,libxl
 - Option in Xen top-level to enable qxl support in qemu tree
 - Fix sse2 MMIO issue
* Polish up xenbugtool
* acpi-related xenstore entries not propagated on migrate
 > http://www.gossamer-threads.com/lists/xen/devel/282466
 > Only used by hvmloader; only a clean-up, not a bug.
 status: Not for 4.3
* mac address changes on reboot if not specified in config file
 > Needs a robust way to "add" to the config
 status: Too much for 4.3
* Default to credit2
* PVIO NUMA improvements
 - NUMA affinity for vcpus
 - PV guest NUMA interface
 - Sensible dom0 NUMA layout
 - Toolstack pinning backend thread / virq to appropraite d0 vcpu
* xenperf
 Owner: Boris Otovsky
* libxl config file
* libxl: Don't use RAW format for "URL"-based qdisks (e.g., rbd:rbd/foo.img)
 - Figure out whether to use a generic URL or have a specific type for each one
 - Check existence of disk file for all RAW
* xl QXL Spice support
* Remove hardcoded mobprobe's in xencommons
 owner: Wei Liu
 status: still in discussion
* xl USB pass-through for HVM guests using Qemu USB emulation
 owner: George
 status: v6 patch series posted
 prognosis: Fair
* Rationalized backend scripts
 owner: roger@citrix
 status: patches posted
 prognosis: Good
* Scripts for driver domains (depends on backend scripts)
 owner: roger@citrix
 status: 
 prognosis: Fair
* Multi-vector PCI MSI (support at least for Dom0)
 owner: jan@suse
 status: Patches posted for Intel; AMD not yet done
 prognosis: Fair
* xl: passing more defaults in configuration in xl.conf
 owner: ?
 There are a number of options for which it might be useful to pass a
 default in xl.conf. For example, if we could have a default
 "backend" parameter for vifs, then it would be easy to switch back
 and forth between a backend in a driver domain and a backend in dom0.
* xl PVUSB pass-through for PV guests
* xl PVUSB pass-through for HVM guests
 owner: George
 status: ?
 prognosis: Poor
 xm/xend supports PVUSB pass-through to guests with PVUSB drivers (both PV and HVM guests).
 - port the xm/xend functionality to xl.
 - this PVUSB feature does not require support or emulation from Qemu.
 - upstream the Linux frontend/backend drivers. Current work-in-progress versions are in Konrad's git tree.
 - James Harper's GPLPV drivers for Windows include PVUSB frontend drivers.
* qemu-based stubdom (Linux or BSD libc)
 owner: anthony@citrix
 status: in progress
 prognosis: ?
 qemu-upstream needs a more fully-featured libc than exists in
 mini-os. Either work on a minimalist linux-based stubdom with
 glibc, or port one of the BSD libcs to minios.
* V4V: Inter-domain communication
 owner (Xen): dominic.curran@citrix.com
 status (Xen): patches submitted
 prognosis: Fair
 owner (Linux driver): stefano.panella@citrix
 status (Linux driver): in progress
* NUMA Memory migration 
 owner: dario@citrix
 status: in progress
 prognosis: Fair
* Event channel scalability
 owner: wei@citrix or david@citrix
 status: RFC v5 submitted
 prognosis: Deciding whether to shoot for 3-level (4.3) or FIFO (4.4) 
 Increase limit on event channels (currently 1024 for 32-bit guests,
 4096 for 64-bit guests)
* PVH mode (w/ Linux)
 owner: mukesh@oracle
 status (Linux): 3rd draft patches posted. 
 status (Xen): RFC submitted
 prognosis: Tech preview only
* blktap3
 owner: thanos@citrix
 status: RFCs posted
 prognosis: Not for 4.3
* Guest EFI booting
 - status: tianocore in-tree, some build problems.
 prognosis: Poor.
 Needs new owner.
* Multi-page net protocol (external)
 owner: ijc@citrix or annie.li@oracle
 status: Initial patches posted (by Wei Liu)
 prognosis: Poor
 expand the network ring protocol to allow multiple pages for
 increased throughput
* Wait queues for mm
 owner: ?
 status: Draft posted Feb 2012; more work to do.
 prognosis: Poor
* Xen EFI feature: pvops dom0 able to make use of EFI run-time services (external)
 owner: Daniel Kiper
 status: Just begun
 prognosis: Probably not for 4.3 (?)
* Persistent grants for net
 owner: annie.li@citrix
 status: Initial implementation not getting expected gains; more investigation requried
 prognosis: Probably not for 4.3
* Serial console improvements
 owner: ?
 status: Stalled (see below)
 prognosis: Probably not for 4.3.
 -xHCI debug port (Needs hardware)
 -Firewire (needs hardware)
* Make storage migration possible
 owner: ?
 status: none
 prognosis: Probably delay until 4.4
 There needs to be a way, either via command-line or via some hooks,
 that someone can build a "storage migration" feature on top of libxl
 or xl.
* Full-VM snapshotting
 owner: ?
 status: none
 prognosis: Probably delay until 4.4
 Have a way of coordinating the taking and restoring of VM memory and
 disk snapshots. This would involve some investigation into the best
 way to accomplish this.
* VM Cloning
 owner: ?
 status: none
 prognosis: Probably need 4.4
 Again, a way of coordinating the memory and disk aspects. Research
 into the best way to do this would probably go along with the
 snapshotting feature.
* xl vm-{export,import}
 owner: ?
 status: none
 prognosis: Prob put off until 4.4 (or GSoC project)
 Allow xl to import and export VMs to other formats; particularly
 ovf, perhaps the XenServer format, or more.
 
* Memory: Replace PoD with paging mechanism
 owner: george@citrix
 status: none
 prognosis: Prob put off until 4.4
* PV audio (audio for stubdom qemu)
 owner: stefano.panella@citrix
 status: ?
 prognosis: ?
* Testing: Network driver domains
* Testing: new libxl w/ previous versions of xl
* Testing: S3
Category:Xen
Category:Xen 4.3