G2 fetching invalid/outdated data

Two users have reported that G2 fetches invalid or outdated data in case a 'query cache' (in MySQL) is enabled and/or GalleryEmbed::done() was not called immediately after a write operation to the G2 database. The problem is apparent if we have a read - write - read sequence on the same object/entity.

We need to investigate and debug the 'storage' layer of G2, where $storage->commitTransaction() is called at the end of a page request or explicitly using GalleryEmbed::done(). However at this time I dont know enough about G2 internals to understand the issue. In depth debugging and discussion with the G2 core devs will hopefully help ... more details will follow ...