CASSANDRA-21505: Fix Harry model CAS IF EQ/NEQ handling of meaningless empty bytes - #5010
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CASSANDRA-21505: Fix Harry model CAS IF EQ/NEQ handling of meaningless empty bytes#5010minal-kyada wants to merge 3 commits into
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+1 from me. We will need to run the tests many times to make sure nothing unexpected happens
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Tried running the repeat job for PaxosV2MultiNodeTableWalkTest, and FullAccordInteropMultiNodeTableWalkTest for 1000 times. Spotted 2 failures which are being separately tracked here https://issues.apache.org/jira/browse/CASSANDRA-21505. |
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The Harry model incorrectly normalized empty bytes to null for all code paths in extract0, causing CAS IF EQ/NEQ conditions to mis-predict, the server compares raw bytes so empty bytes stored for meaningless-empty types correctly satisfies an empty bytes condition, but the model predicted otherwise.
Fix adds a preserveEmpty flag to extract/extract0, scoped exclusively to CAS IF EQ/NEQ conditions. All other paths are intentionally left unchanged as they rely on the existing null normalization.
patch by @minal-kyada ; reviewed by @dcapwell @bdeggleston for CASSANDRA-21505
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