HIVE-27328: Acid dirCache is not invalidated in TezAMs while dropping table #6309
+106
−6
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What changes were proposed in this pull request?
See jira for initial analysis.
The patch introduces a table createTime check while using the acid dir cache. This create_time property is propagated to the TezAM in the vertex-level JobConf, making it able to invalidate stale entries that belong to the previous instance of the same table (before DROP).
An RPC call-based solution wouldn't work because HS2 has no such interface to the AMs, and introducing such functionality to the TezClient/DagClient would be an epic hack, so it's not an option.
Why are the changes needed?
Because stale cache can cause problems, that are hard to investigate and that weren't taken care of by HIVE-26060.
Does this PR introduce any user-facing change?
No.
How was this patch tested?
Manually tested with minihs2.
looking for log entry in the AM log: