Gerrit: 2021 in review

Yet another year has passed for the Gerrit Code Review project with many challenges posed by the COVID-19 pandemic, new exciting releases, and the most popular Gerrit User Summit with the largest audience ever in its 12 years of history.

2021 in numbers

  • 93 registered attendees to the Gerrit Virtual User Summit 2021, connecting from 56 companies over 17 countries, 14 talks showcased by 15 presenters over 2 days
  • 1 Gerrit Contributors’ Summit
  • 35 releases of which 2 major versions (v3.4.0 and v3.5.0.1) and 33 patches
  • 107 contributors from 32 organizations, merging 4763 changes to 84 projects

The Gerrit Code Review community has shown resiliency during these difficult times, with outstanding participation in the events organized during the year, all remote and lacking the much-needed face-to-face interaction.

  • Commits: -26%
  • Projects: -16%
  • Contributors: -30%
  • Companies: -41%
  • Average changes/contributor: +10%

The engagement has paid its toll after two years of pandemics with fewer organizations willing to invest time in contributing to Gerrit, possibly also impacted by the uncertainty of the future. 2021 has also been the first whole year of the project without David Pursehouse, one of the Gerrit project’s top #3 contributors. He was used to contributing 1.5k changes per year, which would alone easily justify the drop observed.

On the bright side, the contributors that continued over the year 2021 have shown an increased commitment as the number of active projects and commits has dropped less than the contributors, increasing the change/contributor rate compared to 2020.

Major organisations contributing to Gerrit in 2021

Google is confirmed to be the leading force of the Gerrit Code Review project, with over 62% of the changes merged, while GerritForge continues to be the #1 top contributor from the rest of the community. There are a couple of pleasant special surprises from the contributors.

  • Wikimedia Foundation confirmed to be the #2 top contributor from the community, all provided by Paladox who has been awarded Gerrit Maintainer in November.
  • SAP continues to be a strong contributor, just below Wikimedia Foundation, with Thomas being awarded Gerrit Maintainer in November.
  • Qualcomm is back on the shortlist of the top maintainers, with many new names in the list of contributors, well done!

Top-ten projects with major activity in 2021

  1. gerrit (2,903 changes)
  2. plugins/code-owners (447 changes)
  3. jgit (287 changes)
  4. plugins/task (83 changes)
  5. plugins/multi-site (57 changes)
  6. aws-gerrit (44 changes)
  7. modules/cache-chroniclemap (40 changes)
  8. plugins/checks (39 changes)
  9. plugins/high-availability (39 changes)
  10. plugins/replication (38 changes)

The first surprise is that the code-owners, the emerging star of the Gerrit plugins, received a massive investment of effort from Edwin (Google), who contributed 89% of the changes to it. The code-owners plugin has also been presented at the Gerrit Virtual User Summit 2021 and attracted the community’s attention.

The second surprise is the decline in contributions in the jgit project during the past two years: from 820 changes/year is now down to 374 changes in 2021.

Task is now the #2 plugin project in terms of merged changes in 2021. Qualcomm keeps the project’s full ownership with 98.9% of changes in 2021.

GerritForge confirm their commitment to improving Gerrit Multi-Site, as its plugin is the #3 in terms of changes merged in 2021.

Aws-gerrit is a relatively new project, presented less than two years ago and contributed by GerritForge, who contributed over 99% of the changes. It confirms to be a very active project that has helped the Gerrit Code Review open-source project deploy and test well-known “recipes” of infrastructure setups and see how Gerrit performs and works on those. Many bugs have been detected before the release and identified by the aws-gerrit project and CI integration.

The cache-chroniclemap module confirms to be very active in 2021, with 40 changes all provided by GerritForge. This relatively new module allows existing Gerrit setups to increase the overall performance of all persistent caches, which are vital in reducing the REST-API latency across all Gerrit features.

The checks plugin was deprecated back in 2020. However, it still shows significant changes and investment from Google in supporting the new Gerrit checks-API and UI. However, the rate of contributions is in stiff decline, down from the 324 changes in 2019 when it was still an actively developed project.

The last two plugins projects in the top tens are the replication and high-availability plugins, which has received major contributions from Qualcomm, GerritForge, Google and Ericsson.

Top events in 2021

The Gerrit Code Review community abandoned the idea of a face-to-face event in 2021 because of the continued global pandemic of COVID-19.
Instead, there were two separate virtual events for sharing the news of what is happening on the platform and the expectations from the community.

Virtual Gerrit Contributors’ Summit – 9th of June

The summit was organized by the Gerrit Community Managers and had an amazing audience amongst the contributors. The presentations showed what different teams are working on and reported into the summit notes:

Gerrit Virtual User Summit 2021 – 2-3 of December

It was the first experiment of an entirely Virtual User Summit of the Gerrit Code Review project history. The challenges were multiple, including the limitations of allowing up to 100s of attendees, shortening the overall time to 3h x 2 days, and still allowing some interactions between the audience and the presenters. After two years of silence, we have finally received some user stories of using Gerrit in the wild.

The Summit has received vast overall positive feedback and rated 7.9/10, making it a fantastic achievement. The quality and interest of the talks were scored even higher, reaching 8.2/10.

The talks have been fully recorded and published on the GerritForge TV channel:

It was definitely a lot of information and sharing, which showed that the Gerrit Code Review open-source project is alive and active more than ever.

Gerrit features highlights in 2021

Gerrit Code Review has major innovations developed and decisions made over 2021. See below a short recap of the ones that represent a turning point in the evolution of the Gerrit open-source project. Some of them are considered breaking changes and, therefore, need careful analysis and a planned upgrade path.

Speed up of Gerrit upgrade from v2.7 to the latest version

2021 has seen a significant increase in the cooperation and contributions of Qualcomm to the rest of the Gerrit Code Review community, focussed on the speed-up of the Gerrit upgrade process from v2.7 to v3.5.
The contributions and cooperation have brought many improvements to JGit and Gerrit and will allow many more companies to migrate faster and smoother than ever before.

Goodbye to Java 8

From Gerrit v3.5 onwards, the source code and binaries of Gerrit Code Review won’t be compatible with Java 8 anymore.

JSch SSH library is completed removed from Gerrit Code Review

The quirks and obsolescence of the JSch library has cursed Gerrit’s destiny for years. Thanks to Thomas Wolf (Paranor) JGit moved away from it and rebuilt all its Git/SSH stack on top of Apache Mina. That has allowed to remove the JSch library from the Gerrit dependencies and used the Apache Mina SSHD client stack instead.

ElasticSearch is removed from Gerrit Code Review

On the 2nd of February 2021, Elasticsearch B.V. changed its license model and abandoned the Apache 2.0 open-source license for the new versions of ElasticSearch v8 and over.

Gerrit cannot include or require any commercial product not released under one of the open-source licenses allowed by the project. The ElasticSearch backend has not been widely used in the community anyway, based on a recent survey sent to the community therefore the ESC decided on the 3rd of November that the ElasticSearch backend will be removed from Gerrit core and moved into a libModule.

Submit Requirements waving goodbye to Prolog

The Gerrit Code Review project does not use anymore Prolog rules for the submit rules of the project from the 16th of December. The support for Prolog-less submit rules is now mature and it will be part of the forthcoming v3.6 release in 2022.

What’s coming in 2022?

The future of Gerrit Code Review is bright and full of innovative ideas and improvements on the overall development and CI/CD lifecycle. With the forced remote working of millions of developers worldwide, more and more companies are looking on how to make remote interactions more useful and fruitful, reducing frictions and making the workflow smoother and faster more than ever.

Stay tuned and keep on using and contributing to Gerrit Code Review, one of the most innovative and productive platforms for code review and collaboration.

Gerrit Virtual User Summit 2021 – Summary and Survey Results

The first Gerrit Virtual User Summit took place online on the 2nd and 3rd of December 2021.
If you have missed the Summit, all the presentations and content are online and is directly pointed by the details of the sessions from the main schedule.
All the recordings of the presentations and associated anonymized Q&A are accessible from GerritForge’s TV channel on YouTube.

The Virtual User Summit format and numbers

The Gerrit Virtual User Summit 2021 was held online to allow most of the community around the globe to attend and share their experience and ideas and avoid the problems with the traveling restrictions due to the COVID-19 pandemic.

Despite the limitations of the remote format, the interest and attendance to the Virtual User Summit has been outstanding, confirming the resiliency of the community and the will to inform and ask questions, share opinions and discuss no matter the difficulties and challenges.

See below some of the numbers of the Summit:

  • 92 registered attendees, with 71 of them showing up at at least one of the two dates (77% of attendance)
  • 17 countries connected (Austria, Canada, China, Czech Republic, Finland, France, Germany, India, Italy, Poland, Portugal, Spain, Sweden, Taiwan, Ukraine, UK, USA)
  • 56 companies
  • 14 sessions in 2 days
  • 15 presenters

Despite the limitations of the remote interaction and the hours, this has been the largest User Summit ever, terrific news for the whole community.

What do people think about the Summit?

All the 71 attendees have received a Survey about the Summit, 24 of them have provided their feedback.

Q1: How would you rate the Gerrit Virtual User Summit 2021 edition?
The average rating has been 7.9 over 10, with the 45% rating 9 to 10 points out of 10.

Q2: What was your main objective in attending the Summit?
Most responses were around “learning about Gerrit’s new features and initiatives” and “getting in touch with the community and its users”.

Q3: Do you consider to have achieved the objective?
88% of the people said “yes”, which seems consistent with the 7.9/10 overall rating of the Summit.

Q4: If your answer was “no”, what is the aspect that was not achieved?
All of them expressed concerns about the inability to have a two-way direct with the other users at the Summit, which is mainly linked to the technical difficulties and limitations of a remote webinar platform.

Q5: How satisfied are you with the quality of the presentations?
The average rating has been 8.2 over 10, with the 55% rating 9 to 10 points out of 10.

Q6: Would you prefer to have your camera on during the Summit as an attendee?
53% answered no, which shows that opinions are divided on the topic of having remote face-to-face communication with such a large audience.

Q7: Would you like to have breakout rooms to interact as part of the Summit?
76% answered yes, giving good confidence of trying that approach in the next Summit, assuming that would be “virtual” again.

Q8: What would be the best way for you to interact with other attendees and speakers during the Virtual Summit?
The majority of the answers were directed to the use of breakout rooms with a moderator, which matches the feedback given on Q7.

Q9: What platform would you suggest to deliver future Virtual Summits?
Most people did not express preferences, while others mentioned Zoom, Google Meet, and GoToWebinar (the one used during this 2021 Summit).

Q10: What did you like the most about the 2021 Summit, and what should be improved in the subsequent Summits?
Most of the people liked the content and quality of the presentations, which matches the high scores given in Q5. Also, the format of 3h per day, split into two different days, looks optimal for compatibility with the existing working day. Registration and attending the event were straightforward, and the browser-based integration with the stream of Q&A was easy.
The proposals for improvements were on the following points:

  • Having more talks about user stories: do people use topics? What they use for CI integration for them? How people vote on changes/topics?
  • Having direct interactions between participants, seeing their faces and talking to them directly
  • More communication and advertisement of the event beforehand
  • More seamless transition between the webinar part and the interactive Q&A session

What’s next for 2022?

With the new Omicron-variant of COVID-19 raging in the UK and the risk of global expansion in 2022, a face-to-face User Summit next year is still possible but unlikely.
The huge success of the Virtual Summit format could lead us to try an improved version in 2022, trying other platforms like Zoom or Google Meet.

Many new exciting features are coming in 2022, including the release of Gerrit v3.6 and the Prolog-less Submit Requirements. We would love to see again what the community thinks about it and interact more with the real-life Gerrit Code Review users and administrators.

Thanks again to those who have participated and presented at the Gerrit Virtual User Summit 2021. See you next year for another exciting and more engaging get-together in 2022!

The Virtual Gerrit User Summit is tomorrow!

Join the Gerrit Community tomorrow and Friday from 8 am PST for everything related to the Gerrit Code Review Community.

Gerrit provides web based code review and repository management for the Git version control system. Whether you are experienced or new to Gerrit, you should know that it provides a framework you and your teams can use to review code before it becomes part of the code base. Come and take this chance to join and learn about Gerrit Code Review.

Find here the full schedule of the sessions you will have access to.

Register and join the community event!

Few days left to the virtual Gerrit User Summit

An important part of the summit are the lightning talks, ten-minute talks that intend to present research or demos and work in progress within the Gerrit Code Review.

Join Ian Gauthier, Flywheel.io who will present research performed to evaluate the extent to which historical data is an appropriate benchmark for reviewer recommendation systems. In another session Paul Jolly, CUE demonstrates how the CUE project uses GerritHub in combination with GitHub Actions for Continuous Integration and regression testing. And don’t miss out the live demo and presentation of the AWS-Gerrit project by Antonio Barone, GerritForge with the integration with AWS X-RAY, as part of the efforts to bring Gerrit to the cloud.

Find more details on the agenda and register here.

Be an active part of the Summit: Last Call for Presentations

There are still a few slots open for you to present on the virtual Gerrit User Summit.

Submit your presentation proposal by creating a change to the Gerrit Summit 2021 repository by following these steps:

  • Login to https://gerrit-review.googlesource.com
  • Go to the Gerrit Summit 2021 repository
  • Click “CREATE CHANGE” button and specify the branch (master) and the headline of your talk
  • Click on “EDIT” button on the top-right to edit your change
  • Click on the “ADD/OPEN/UPLOAD” button and enter the filename for your talk (e.g. sessions/super-duper-repos.md for a talk or lightning-talks/mini-session.md for a lightning talk) upload the text for your talk by dragging the markdown text into the window.
  • Click the “PUBLISH EDIT” button on the top-right of the change screen
  • Click on the “MARK AS ACTIVE” button on the top-right of the change screen

Your talk will then be reviewed by the community and, when accepted, merged into the Gerrit User Summit 2021 site.

Don’t miss out!

Gerrit User Summit is calling: submit your presentation

The Gerrit Code Review community invites you to participate at the virtual Gerrit User Summit 2021 scheduled to take place online on the 2nd and 3rd December, from 8 am to 11 am PST.

This year’s program will offer a keynote, six presentation sessions and seven ‘lightning’ (10-minute) talks distributed in two days, so that you can share your ideas, research, demonstrations, live demos, and network with the Gerrit Community and those interested in learning and adopting Gerrit Code Review in their development process.

Submit your presentation proposal by creating a change to the Gerrit Summit 2021 repository by following those steps:

  • Login to https://gerrit-review.googlesource.com
  • Go to the Gerrit Summit 2021 repository
  • Click “CREATE CHANGE” button and specify the branch (master) and the headline of your talk
  • Click on “EDIT” button on the top-right to edit your change
  • Click on the “ADD/OPEN/UPLOAD” button and enter the filename for your talk (e.g. sessions/super-duper-repos.md for a talk or lightning-talks/mini-session.md for a lightning talk) upload the text for your talk by dragging the markdown text into the window.
  • Click the “PUBLISH EDIT” button on the top-right of the change screen
  • Click on the “MARK AS ACTIVE” button on the top-right of the change screen

Your talk will then be reviewed by the community and, when accepted, merged into the Gerrit User Summit 2021 site.

Gerrit User Summit 2021: how to tackle big mono-repos

GerritForge keeps working to improve performance using Gerrit with very large mono-repos with millions of refs, hundreds of GBs and tens of millions of objects.

On the second day of the virtual Gerrit User Summit 2021, Luca will present the work done over the past two years to overcome significant difficulties when:

  • Reducing the overhead of refs advertisement
  • Speeding-up clones by a 10x factor
  • Reducing the system load when accessing change notes
  • Increasing performance of replication
  • Surviving the deadly “search-for-reuse” phase during git-upload-pack

Register here to join the user summit on December 2nd and 3rd.

SAVE THE DATE: Gerrit User Summit is back on 2 & 3 Dec 2021

REGISTRATION is open to the Virtual Gerrit User Summit. It will take place on 2nd and 3rd December 2021 https://gerrit.googlesource.com/summit/2021/+/refs/heads/master/index.md

The Gerrit Community is happy to announce the Gerrit Virtual User Summit 2021, THE event of the year for everything related to Gerrit Code Review and the trunk-based development pipeline.

A Virtual Summit

The Gerrit User Summit 2021 will be held online only, to allow most of the community around the globe to attend and share their experience and ideas, and avoid the problems with the travelling restrictions due to the COVID-19 pandemic.

The 2-day User Summit is open to all the members of the community as well as those that are willing to learn and adopt Gerrit Code Review in their development process.

Summary of the Gerrit User Summit & Hackathon in Sunnyvale

sunnyvale-gerritforge-live.jpg

After months of reviews and contributions by different speakers and attendees, the summary of the last Gerrit User Summit & Hackathon in Sunnyvale CA has been published on the Gerrit Code Review News page.

High-performance Summit in numbers

The Gerrit User Summit 2019 has ended, with highest score of achievements
in the history of the 11 years of the entire Gerrit open-source project:

  • Two dates and locations in a 12-months period: Gothenburg (Sweden) and
    Sunnyvale (California).
  • Four Gerrit releases delivered: v2.15.16, v2.16.11, v3.0.2, v3.1.0
  • 127 people registered across the two locations,
    87 people attended on-site (70% turnout) and 38 people followed the event
    remotely at different times using the live streaming coverage
    provided by GerritForge.
  • 373 changes merged (204 in Gothenburg, 169 in Sunnyvale).
  • 32 developers attended the Hackathons, 8 of them have never contributed or
    attended an event before.
  • The highest performing version of Gerrit v3.1.0 released, with over
    2x git and REST-API performance compared to v3.0.x.
  • 22 talks presented across Gothenburg and Sunnyvale, with 6 new speakers
    that have never presented before at the Summit.

The performance of the Summit is yet again another evidence of the continuous
growth of the community and the increased synergies with the JGit, OpenStack/Zuul
and the Tuleap open-source projects.

Read the full Summit and Hackathon summary on the Gerrit Code Review web-site.

Gerrit User Summit Survey

The 2019 has been an exceptional year, with the introduction of the next generation of Gerrit Code Review v3 releases and the largest ever Gerrit User Summit in the whole history of 11 years of the project.

As a community we want to improve even further and make the project and the community even better. Collecting metrics has been key for the improvements of the Gerrit product and its performance and, similarly, collecting feedback from the community events is the key to grow and increase the participation and sharing of the experiences about Gerrit Code Review.

Survey results

We have run a survey directed to all of those who have attended the two Gerrit User Summits this year, in Gothenburg and Sunnyvale. See below the executive summary of the results.

Did you achieve your objectives at the Summit?

Screenshot 2019-12-23 at 08.41.14

All of the attendees achieved their objective, which were different for the people, depending on their position and role in the community.

  • Getting the latest news of what’s happening in the Gerrit community and open-source product
  • Meeting the existing members of the community and welcome new contributors
  • Networking with the other Gerrit admin and users around the world
  • Influencing with ideas the future Gerrit roadmap

Overall, how would you rate the event?

Screenshot 2019-12-23 at 08.47.44

Over 76% of the people rated the event very good or excellent. However, as we strive for improvement, there is a substantial 24% of of people that are looking for a better event next year.

What did you like/dislike?

The positives of the event have been:

  • Presentation of the Gerrit roadmap and associated discussions
  • Successful mix of topics, including Zuul and JGit
  • People, atmosphere, friendship and networking
  • High quality of the talks and content

The not so positive sides where:

  • The summit covering the weekend
  • Too focused on Gerrit contributors and admins, no space for users
  • There was too much people for the chosen location
  • The talks and discussions went over the planned schedule

How organized was the event?

Screenshot 2019-12-23 at 08.56.17

89% of the people considered the event very well organized, whilst 11% are looking for improvement, possibly with a bigger venue and better timing.

What topics would you like to see covered next year?

  • Evolution of the User-Interface, roundtable with developers, user-journeys
  • Migration talks and discussions
  • CI/CD integration
  • Monitoring
  • Load testing
  • GitHub integration and pull-requests
  • Gerrit with large clusters
  • User-stories on using Gerrit

Would you like to have a workshop next year?

Screenshot 2019-12-23 at 09.02.56

The vast majority of people would like the next year event to be more informative, including a workshop for learning some of the features of Gerrit Code Review.

What would be the best time for the Summit next year?

Screenshot 2019-12-23 at 09.04.47

For the majority of people (75%) the best time for next year event would be two days during the week, rather than having it again over the weekend.


Thanks everyone again for attending the Gerrit User Summit 2019 in Gothenburg and Sunnyvale, and thanks to GerritForge, Volvo Cars and Google for sponsoring it. We are looking forward to seeing you next year.

Luca Milanesio (GerritForge)
Gerrit Code Review Maintainer, Release Manager and ESC Member.