Background

A learner’s grades are calculated by aggregated scores across individual XBlock usages. In the old days, grades would be recalculated from scores on-demand, every single time. This caused serious performance limitations around grade display, editing, reporting.

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Starting in Olive, persistent grades are enabled by-default. There is no option to disable them. This simplifies LMS feature development, but it does require that all operators run the backfill (described below) as part of their Olive upgrade if they have not already enabled persistent grades. The backfill can be run before or after upgrading to Olive.

The Persistent Grades Backfill

Here's how we did it for edx.org.  Note that you could do things somewhat differently; for example, you could backfill grades for a subset of courses at a time (using the --courses flag) instead of all your courses.

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