Primer problema de MySQL en los 12 años de vida de este blog:

MariaDB [drupal7]> select * from semaphore;
ERROR 144 (HY000): Table './drupal7/semaphore' is marked as crashed and last (automatic?) repair failed
MariaDB [drupal7]> repair table semaphore;
+-------------------+--------+----------+----------------------------------------+
| Table             | Op     | Msg_type | Msg_text                               |
+-------------------+--------+----------+----------------------------------------+
| drupal7.semaphore | repair | warning  | Number of rows changed from -2032 to 0 |
| drupal7.semaphore | repair | status   | OK                                     |
+-------------------+--------+----------+----------------------------------------+
2 rows in set (0.00 sec)

MariaDB [drupal7]>

Hasta hoy yo estaba convencido de que era irrompible.