| The information on this page refers to License Statistics v5.15 or newer, which upgraded MySQL to v5.7. If you are using an earlier version of License Statistics, please refer to the documentation for releases prior to v5.15. |
Issues with MySQL migration
If insufficient disk space was reserved for MySQL prior to migrating the License Statistics database to License Statistics 5.14, the migration marked in the log as 3.1.4 will not execute properly. MySQL terminates the CurrentFeatureUsage sorting query during the disk space allocation phase, a few minutes after migration begins. The Java process is unable to detect the unexpected query termination state, and continues to wait for data from MySQL that is never sent.
When this issue occurs:
- There is no visible resource consumption (CPU, RAM) a few minutes after migration has started, and no queries running on the MySQL side.
- Migration does not continue, and after a couple of hours, fails on exceeding the mysql_timeout value.
- The following entries can be seen at the end of the core.log file:
2019-03-24 16:26:52.210 | INFO | main | o.f.c.i.u.l.s.Slf4jLog | Migrating schema `xformation_licstat` to version 3.1.4 - Migrate data from CurrentFeatureUsage table
2019-03-25 00:29:01.525 | WARN | main | c.m.v.l.s.Slf4jMLog$Slf4jMLogger$WarnLogger | SQL State '08007' of Exception tested by statusOnException() implies that the database is invalid, and the pool should refill itself with fresh Connections.
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<< Rest of the stack trace >>
To avoid this issue, make sure you have sufficient disk space prior to migrating; specifically:
- The available space in the mysql data directory should be at least twice your current database size.
- The available space in the mysql temporary location should be at least twice your current database size.
Embedded MySQL server troubleshooting
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