The talk is a status report for the latest release and development projects. It will cover the new features and important bug fixes (if any) in 4.7. It will also provide insight on what’s in the queue for the next major release. Retrospective on the release process will also be part of talk.

1. Wei Liu
Release Manager, Committer liuw
Presented by
Lars Kurth & George Dunlap

2. Refresher: Xen Release process
Xen 4.7 Update
Xen 4.8 Development Update

4. Reduce release cycle length to 6 months:
– 4 months development
– 2 months freeze, with earlier creation of release branch based on risk assessment
– Xen 4.7 was longer to support future June / December releases
Dec Jan Feb Mar Apr May Jun Jul Aug Sept Oct Nov Dec

5. Master branch on xen.git
Feature Development
Feature
Freeze
point
Wait period
to clear test pushgate
RC’s
Release
Announcement
RELEASE-4.7.0 branch on xen.git
RELEASE-4.8.0 branch
based on risk assessment
Last
Post
Date

6. Master/Release branch on xen.git
Wait period
to clear test pushgate
RC’s
No new features
No Freeze Exceptions
Bug fixes are allowed, with approval by Maintainers/Release Manager
Release Manager declares that only bug fixes deemed blockers can be accepted
Creation of RELEASE-4.8.0 branch based on risk assessment
Feature Development
This is when patches for the ongoing release
need to be submitted for review

7. Release Manager:
Sends Monthly
Xen x.y Development Update
email on xen-devel@
Contributors:
Expected to reply if they are working on a feature that is not
on the list of tracked features
Expected to provide Status updates on features & bugs on the list
Not engaging with the process may lead to removal or downgrading
Release Manager:
Sends first
Xen x.y Development Update
email on xen-devel@
Deferred features from previous
release, Timetable, etc.
Contributors:
Expected to reply if they are working on a feature that is not
on the list of tracked features and tracked bugs
Release Manager:
RC Announcements, Test Days
Contributors:
Expected to provide Status updates on tracked bugs on the list
Release Manager:
Release Announcement

8. Xen code base
 Hypervisor: general, x86 and ARM
 Toolstack
 Others upcoming things
Test lab / Testing
Guest OS support

10. First fixed term release
actually 9 months cycle
 Development start: 9 September 2015
(branched early; 4.6 released Oct 5th)
 Freeze: 8 April 2016
 Release date: 20 June 2016
Goals: predictable releases
But take into account exceptional situations
 Several XSAs
 Wanted to include LivePatching
 2 weeks overdue, but still acceptable

11. KConfig support …
Improved Virtual Machine Introspection subsystem …
Credit2 scheduler improvement …
RTDS scheduler improvement
 converted to event-driven model
 support per-vcpu parameter
Per-cpu reader-writer lock to improve performance

12. Hypervisor live patching …
CPUID leveling
PV guest memory limit bumped to TB range
Intel VT-d Posted Interrupt
Intel Code and Data Prioritization
Intel VMX TSC Scaling
Intel XSave/Xrtors support
Intel Memory Protection Keys

13. Server Base Boot Requirement compliance
PSCI 1.0 compatibility
ARM vGICv3 support
Support getting wallclock directly from Xen
Bug fixes for existing platforms

14. PVUSB support
Hot-plugging of QEMU-backed disks
Soft-reset support
Building and migrating large PV domain
libxenctrl broken into a set of stable libraries
Coarse-grained Lock-stepping Xen part upstreamed

15. Added lines: +86378
Removed lines: -28012
Lines of changes: +58366
Changes/month 230
Changesets (Patches) 1887
Series (=Features) 1025
Review Comments: 11628
1.84 patches per series
11.3 comments per series

16. Xen 4.8
first short fixed term release
6 months cycle
Jun Jul Aug Sept Oct Nov Dec
Jun 6
Last Posting Date
Sept 16
Code Freeze
Sept 304.7 4.8

17. PVHv2/HVMLite DomU and Dom0
Livepatching for ARM …
IOREQ server for XenGT
Loading arbitrary firmware blob via toolstack
vNVDIMM support …
Libxl PVSCSI support
Depriviledged QEMU
Mini-OS balloon driver support
Mini-OS PVHv2/HVMLite mode support
Restartable Dom0
and more ...

18. Removal of Blktap2
Cleanup of COPYING files (and other license related cleanup)

19. ARM 64 Bit Machines
2x Softiron Overdrive 3000
2x Gigabyte R150-T61 (if we can get them in time)
OSSTEST
Work to integrate XTF into OSSTest underway
Work to improve OSSTest throughput underway

20. Linux
Experimental support in Xen for ACPI on ARM64 machines
Xen wallclock support in Xen and Linux on ARM and ARM64
Xen stolen ticks support in Xen and Linux on ARM and ARM64
Many GICv2 and GICv3 correctness improvements in Xen
Netback dynamic multicast control support
Blkback multiqueue support
Dozens other fixes and minor improvements

21. FreeBSD
Netfront multiqueue support
Blkback support for hotplug scripts
Fixes for clock skew during suspend / resume
Netfront packet forwarding fixes
Mini-OS
Ballooning support
Build system fixes and cleanup

22. It relies on YOU engaging
with the Release Process