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The receive() method was incrementing the local node's vector clock entry twice: once during merge() (which takes the max of both clocks) and again with an explicit increment(). This inflated the local node's clock value on every receive, breaking causal ordering guarantees. The standard HLC receive algorithm only merges clocks and updates logical_time — the local node's entry should not be incremented separately during receive. Fixes hetu-project#22
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Summary
Fixes #22
Problem
The
VLCSnapshot::receive()method incremented the local node's vector clock entry twice:merge()takes the component-wise max of both clocks (correct)vector_clock.increment(local_node_id)adds +1 on top of the merged value (incorrect)This inflated the local node's clock on every receive operation, breaking causal ordering. A node that received many events would have artificially high vector clock values, causing incorrect concurrency detection.
Standard HLC receive algorithm:
Fix
Removed the extra
self.vector_clock.increment(local_node_id)call fromreceive(). The local node's clock is already correct after merge — it only needs incrementing during localtick()operations.