Xen Project 4.9 Acknowledgements

Note that the acknowledgements have been created based on 4.9.0-rc7, which is expected to be the final RC for Xen 4.9.0 (with the exception of some security fixes under embargo). If there is another release candidate, data needs to be updated.

Overview

As we have made significant changes to the xen source tree structure, we will count acknowledgements in line with RFC Xen 4.6 Acknowledgements.

The following table compares Xen 4.8 with Xen 4.9. We also cover changes to Xen only components in Linux, FreeBSD, NetBSD and QEMU in the "Drivers and Devices" column, which are primarily made by Xen Project developers. Note that the number is not part of the 4.9 Hypervisor Total.

Attribute	4.8 Hypervisor Total [ 1 ]	4.9 Hypervisor Total [ 1 ]	4.9 Hypervisor Core[ 2 ]	4.9 Hypervisor Other [ 3 ]	Drivers and Devices (other projects)[ 4 ]
Release Cycle	255 days 197 dev window/days[ 6 ] 8.4 months	161 days 124 dev window/days[ 6 ] 5.3 months
Development Velocity
Changesets	1887	1245	967	278	321
Series (=Features) [ 5 ]	1025	575
Average Size of Feature	1.84	2.17 (+15%)
Changes / Day	7.5	7.7 (+3%)
Changes / Dev Day [ 6 ]	9.6	10.0 (+4%)
Features / Day [ 5 ]	4.0	3.6 (-11%)
Code Review Statistics
Review Comments [ 5 ]	11628	6854
Review Comments / Day [ 5 ]	45.6	43.6 (-4%)
Comments / Series [ 5 ]	11.3	11.9 (+4%)
Code Churn
Lines Added	106606	78899	70833	8066	18421
Lines Removed	37160	62325	59502	2823	13775
Engagement
Individuals	102	68	68	5	59
Employers	36	34	33	4	37

4.9 Hypervisor Only Code Contributions ^{[ 2 ]}

Breakdown by Individual

To Do: Insert data - will have to do this post the 4.9 release

This table is sortable : please click on the icon besides the column header, to sort by a specific column.

Name	Lines Added	Lines Removed	Changesets

4.9 Hypervisor Related Code Contributions ^{[ 3 ]}

Breakdown by Individual

Note that the table below does not cover contributions to Linux, NetBSD, FreeBSD, QEMU, libvirt and other related projects. It lists contributors to mini-os (formerly part of xen.git), osstest (our test code and test cases), raisin (a deployment and test tool), xtf.git and livepatch-build-tools (tools to builld livepatch payloads).

This table is sortable : please click on the icon besides the column header, to sort by a specific column.

Name	Lines Added	Lines Removed	Changesets

Code Contributions to Xen Related Drivers and Devices in Linux, NetBSD, FreeBSD ^{[ 4 ]}

Breakdown by Individual

To Do: Insert data - will have to do this post the 4.9 release

This table is sortable : please click on the icon besides the column header, to sort by a specific column.

Name	Lines Added	Lines Removed	Changesets

4.9 Hypervisor Reviewers ^{[ 5 ]}

To Do: Insert data - will have to do this post the 4.9 release

This table is sortable : please click on the icon besides the column header, to sort by a specific column. Note that in the table below, we only count review comments by community members other than comments by the author of a patch. We do not count replies and clarifications by the author of a patch that are made in response to review comments by others.

Name	Review Comments

Footnotes

^{[ 1 ]} Includes the following repos: xen, mini-os, osstest, raisin, livepatch-build-tools, xtf
^{[ 2 ]} Includes the following repos: xen
^{[ 3 ]} Includes the following repos: mini-os, osstest, raisin, livepatch-build-tools, xtf
^{[ 4 ]} Includes commits to the following Xen specific directories of the following upstream projects: linux: arch/*/xen/ arch/*/include/asm/xen/ drivers/xen/ drivers/*/*xen* include/xen/ arch/*/pci/*xen* ; netbsd: sys/arch/xen; freebsd: sys/dev/xen/ sys/x86/xen sys/xen/; qemu: xen* hw/i386/xen hw/xenpv hw/*/xen* hw/xen include/*/xen*, xen windows pv drivers
^{[ 5 ]} This data was extracted from the Xen Project Code Review Dashboard
^{[ 6 ]} These are the days/months during which we were not in code freeze