Does MindProbe have a build we can test for concurrent participant assignment?
In a test on MindProbe running JATOS 3.11.3, two participant sessions requested different assignments at the same time. Both received a success response, but only one assignment appeared in the final batch data.
Our tests passed locally on a newer JATOS build that includes atomic version-checked writes (0c569846) and fresh participant batch-session reads (0c89f7ce). Is a build with both changes available on MindProbe or on a staging instance where we can test using signed-out participant links?
Comments
Thanks for testing this! The race in 3.11.3 can happen when two participants submit batch-session updates close enough together that both requests read the same version before either write is saved. In that case, both can report success even though one overwrites the other.
Both fixes you tested will ship with JATOS 4.0, a major rewrite that still needs more testing. I’m aiming for January 2027 for the release.