tree cae24fe5e408594cee4036ac1eb25a18862ca696
parent 03bcbc7b9e3ae9eaac5f11a67941538f329998e2
author Luca Milanesio <luca.milanesio@gmail.com> 1608166055 +0000
committer Luca Milanesio <luca.milanesio@gmail.com> 1608242548 +0000

Lock on index element id rather than on index task id

The execution of concurrent reindexing operations
to the secondary Gerrit servers was erronously using the
task id rather than the index id (index type / element id).

That caused the possibility of concurrent conflicting reindexing
operations (e.g. indexing Change ABC and removing it at the same
time).

Even though this concurrency was very unlikely to happen, it could
actually be possible when the reindexing was going through a series
of retry cycles.

Create specific IndexEventLocks concurrency tests to highlight
this and future concurrency issues with the locking mechanism.

Bug: Issue 13835
Change-Id: Ic6d7d1ad227d08277fd8f246ddd26bf241830c6b