SourceForge changes to CVS service

I just received a mail that comes with great news about SourceForge CVS service. However, it will require some changes in the way we are currently accessing the CVS (project checkouts, annonymous exports, and so on).

Even if you're not administering a SF.net project, I think it might be of your interest to read what SF.net staff has emailed to project administrators (you might need to update your CVS client).

Here's the news:

One of SF.net primary services, CVS, suffered a series of interrelated, critical hardware failures in recent weeks. We understand how frustrating this CVS outage must be to you and your users; however, our top priority remains preservation of the integrity of your data.

The series of CVS hardware failures prompted us to expedite the deployment of planed improvements to our CVS infrastructure, drawing upon much of the knowledge that we gained from our Subversion deployment. Our improved CVS service architecture, which we plan to deploy tomorrow afternoon (2006-05-12), will offer greater performance and stability and will eliminate several single points of failure.

The Site Status page will be updated as soon as the new infrastructure is rolled out. In the interim, please read the important information provided below to learn about how these changes will affect your project.

Summary of changes, effective 2006-05-12:

• Hostname for CVS service

  Old: cvs.sourceforge.net

  New: PROJECT_UNIX_NAME.cvs.sourceforge.net

  This change will require new working copies to be checked out of all repositories (so control files in the working copy will point to the right place). We will be updating the instructions we supply, but instructions that your team has written within documentation, etc. will need to be updated.

  cvs -d:pserver:anonymous@cvs.sourceforge.net:/cvsroot/gaim co gaim


  would be changed to

  cvs -d:pserver:anonymous@gaim.cvs.sourceforge.net:/cvsroot/gaim co gaim


   

• ViewCVS

  We are moving from ViewCVS to its successor, ViewVC. ViewVC is currently in use for our Subversion service.

• Sync delay

  Old: CVS pserver, tarballs and ViewCVS provided against a separate server which is a minimum of three hours behind developer CVS.

  New: ViewVC will be provided against developer CVS (it will be current). CVS pserver will be provided against a secondary server (not developer server) with a maximum expected delay of two hours.

  Follow-up work is planned (this infrastructure takes us 80% of the way) to essentially eliminate the sync delay.

• Read-only rsync service

  As a new service offering, we are now providing read-only rsync access against developer CVS. This allows projects to efficiently make on-demand backups of their entire CVS repository.

  All projects should be making regular backups of their CVS repository contents using this service.

• Nightly tarball service

  Nightly tarball service is being dropped in lieu of read-only rsync service. Projects which currently depend on nightly tarballs for repository backups will need to begin using rsync to make a backup copy of their repository contents.

  We see this as a major functional improvement. For a number of reasons, tarballs have fallen out of sync with the data in the repository at times in the past few years. Tarballs required a substantial amount of additional disk, and I/O to generate. The move to read-only rsync allows backups to be produced on-demand, with an update frequency chosen by the project.

• Points of failure

  In the past, developer CVS service for all projects was provided from a single host. CVS pserver service was provided from individual backend heads based on a split of the data.

  Under our new design, developer CVS and most of our CVS-related services are provided from one of ten CVS hosts (count subject to increase with growth). Each host is independent, and makes a backup copy of the repository data of another host (which is used to provide the pserver CVS service).

  Failure of a single host will impact only the availability of data on that host. Since the data is split among a larger number of hosts, the size of data impacted by an individual host outage is substantially smaller, and the time required for us to restore service will be substantially shorter.

  This rapid architecture change has been made possible specifically using the research we performed for our recent launch of Subversion service. We've applied our best practices, produced a substantial amount of internal documentation, and kept an eye toward maintainability. This effort has allowed us to deploy this new architecture quickly once hardware was received, and will permit us to quickly scale this service horizontally as growth and demand requires.

Many other minor improvements have also been made to improve the service offering and make it less trouble-prone. The most important of which are listed above. For a full description of the new SF.net CVS service, and for information on how to use the services described above, please refer to the site documentation for the CVS service after the service has been launched.