Status of Bugzilla Migration

Dear All,

I would like to give you the status update of our bugzilla migration.
First of all, unfortunately it was affected by the major GitHub outage
that happened over the weekend and our schedule was delayed a bit as
we have to wait until the outage ended, have to restart the import and
also GitHub support engineers that watched our migration were moved to
fix the issues of the service.

As of now we're having:
  - All bugzilla content is imported to the bugzilla archive GitHub
repo: https://github.com/llvm/llvm-bugzilla-archive/issues
  - All issue numbers are preserved wrt this repo. This means that
Bugzilla PR 1234 could be found at
https://github.com/llvm/llvm-bugzilla-archive/issues/1234. This repo
will be the basis of our stable numbering of the issue id's.
  - The llvm.org/PR redirect is installed. It will redirect to
bugzilla archive for all PRs with ids <= 52601 and to the main
llvm-project for everything else
  - The llvm.org/bz redirect is installed. Links like llvm.org/bz1234
will forward to the read-only bugzilla instance

The last remaining step is the transfer of the issues from bugzilla
archive to the main llvm-project repo. This way we will have all the
issues in the single repo (albeit with different numbers, this is kind
of compromise we have to accept as we can ensure the preservation of
the issue numbers only on the empty repo and we cannot lose the
releases, etc. on the existing repo, however, the URLs relative to the
archive repo will allow us to keep the original bugzilla issue numbers
and also, github will rewrite all references inside the comments for
us).

This step is in some sense final - we cannot undo it since we'll start
doing this. Also, while the import of issues to the empty repo does
not trigger any notifications, the transfer will trigger all kinds of
notifications. We certainly do not want that everyone who contributed
to any issue in the past would receive multiple notifications. For
some active community members the volume of notifications would be
excessive – thousands of emails.

GitHub has a way to disable notifications, however, they found some
issues with it pretty recently. We are waiting for them to resolve it
and expect the final migration to happen within the next 48 hours.

Thanks for the update!

Hi Mehid,

Something isn't clear to me here and I'm concerned about this setup: how are we gonna go from the "archived number" to the "real" monorepo issues?
I don't even understand the need for the archive repository right now: why can't we just redirect llvm.org/PR to the monorepo issue?

I hope we don't lose this mapping, that seems quite critical to me.

Sorry for not being 100% clear as this is a bit tricky :slight_smile:

After the transfer from archive repo to the llvm-project, the issues
will be renumbered and there is no way to control this (sick!).
However, GitHub will maintain the mapping for us and enable the
redirect.

E.g. assume that the original bugzilla issue 12345 will be transferred
to llvm/llvm-project/issues/45678. It would seem that the original
number is lost, however, it will not: llvm/llvm-bugzilla-archive/12345
will redirect to llvm/llvm-project/issues/45678. So, llvm.org/PRNNNN
will redirect to the final monorepo issue regardless whether it was
from bugzilla or the "new" github-only variant (it redirects to
archive for "low" NNNNN numbers and to monorepo for everything else).
Also, during the transfer all github-internal issue links will be
updated, so all references to #12345 will be rewritten to the new
monorepo issue id.

Hope this is a bit more clear now.

Hi Mehid,

Something isn’t clear to me here and I’m concerned about this setup: how are we gonna go from the “archived number” to the “real” monorepo issues?
I don’t even understand the need for the archive repository right now: why can’t we just redirect llvm.org/PR to the monorepo issue?

I hope we don’t lose this mapping, that seems quite critical to me.
Sorry for not being 100% clear as this is a bit tricky :slight_smile:

After the transfer from archive repo to the llvm-project, the issues
will be renumbered and there is no way to control this (sick!).
However, GitHub will maintain the mapping for us and enable the
redirect.

E.g. assume that the original bugzilla issue 12345 will be transferred
to llvm/llvm-project/issues/45678. It would seem that the original
number is lost, however, it will not: llvm/llvm-bugzilla-archive/12345
will redirect to llvm/llvm-project/issues/45678. So, llvm.org/PRNNNN
will redirect to the final monorepo issue regardless whether it was
from bugzilla or the “new” github-only variant (it redirects to
archive for “low” NNNNN numbers and to monorepo for everything else).
Also, during the transfer all github-internal issue links will be
updated, so all references to #12345 will be rewritten to the new
monorepo issue id.

Hope this is a bit more clear now.

Thanks! Very clear and addressing my concern perfectly :slight_smile: