https://www.spinellis.gr/blog/20191103/

The progress indicator of MySQL or MariaDB long-running commands and queries is extremely extremely and frustratingly coarse. In an index update I’m running now it was stuck in the same state for more than three hours. Thankfully, the pmonitor tool allows us to precisely monitor the progress of many commands. Here’s an example of its application on MariaDB.

Adding an index on a GHTorrent table with 6 billion records seemed to take forever, stuck in the “Enabling keys” state.

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