Invalidate the Prepared statement cache only if either of the prepare…#4542
Invalidate the Prepared statement cache only if either of the prepare…#4542jaydeepkumar1984 wants to merge 1 commit intoapache:cassandra-4.0from
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| else if (cachedWithoutKeyspace != null || cachedWithKeyspace != null) |
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I think we need something like else if ((cachedWithoutKeyspace != null) != (cachedWithKeyspace != null)), to make sure at least one of them is in cache.
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Let me elaborate.
boolean safeToReturnCached = cachedWithoutKeyspace != null && cachedWithKeyspace != null;
We are in the else block because safeToReturnCached is false. If safeToReturnCached is false, that means either cachedWithoutKeyspace is null or cachedWithKeyspace is null or both of them.
So, at this place, if (cachedWithoutKeyspace != null || cachedWithKeyspace != null) is sufficient.
Could you please double-check?
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@jaydeepkumar1984 thanks for elaborating, I think you're right.
Just as a nitpick, and if you get a chance, could you add a short comment saying "only evict if we know one of the statements is cached".
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Incorporated
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| else if (cachedWithoutKeyspace != null || cachedWithKeyspace != null) |
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@jaydeepkumar1984 thanks for elaborating, I think you're right.
Just as a nitpick, and if you get a chance, could you add a short comment saying "only evict if we know one of the statements is cached".
…d caches is empty, but not both
jaydeepkumar1984
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https://issues.apache.org/jira/browse/CASSANDRA-17248 added prepared statement eviction logic because there was a change in prepared statements' behavior between 4.0.1 -> 4.0.2. However, the eviction logic introduces a race condition depicted in https://issues.apache.org/jira/browse/CASSANDRA-17401
As per this discussion, we should keep the eviction logic in the 4.0 branch, but invoke only in a real corner case scenario.
This PR will evict the statements only during the corner case scenario in which either of the prepared statement caches is empty, but not both.
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