FLUSH STATISTICS blocked by starving historization query in logserver
Details
| Detail name | Value |
|---|---|
| Changelog Number | 7847 |
| Type | Bug |
| Status | Resolved |
| Affected Versions | Exasol 6.1.0 |
| Fix Versions | Exasol 6.1.4 |
| Resolution Date | 2019-06-12 |
Background
The logserver does collect and historize statistics like profiling and monitoring data. The historization uses regular SQL statements.
Problem
From time to time, the profile historization is stuck for hours. The process somehow recovers after some time but still finishes in hours instead of seconds.
While the logserver is occupied with historization tasks, any FLUSH STATISTICS statement from user sessions is blocked until the historization finishes. Auditing and profiling data will not be updated until the historization is done.
Workaround
There is no known workaround so far.
Fix
The bug of starving statistics historization needs to be fixed.
