Fixed race condition in query cache to avoid potential system deadlocks
Details
| Detail name | Value |
|---|---|
| Changelog Number | 20461 |
| Type | Bug |
| Status | Resolved |
| Affected Versions | Exasol 8.0.0 |
| Fix Versions | Exasol 8.29.10, Exasol 2025.1.0 |
| Resolution Date | 2025-05-15 |
Description
In rare scenarios, a race condition in the query cache can cause a system deadlock, eventually leading to a DB restart. This could only happen if the query cache is heavily used and the size of the query cache is not large enough to store all active query results. This problem has been fixed.
Workaround
Disable the query cache. This can be done by adding the DB parameter "-useQueryCache=0" (see Adding Database Parameters).
Fix
An optimization in the query cache has been disabled to fix this issue. No measurable effect on performance is expected.
