relax drift? to match the paper and unburden the client#22
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NeilMenne
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May 28, 2026
1. Relax recv max drift to check only `l - pt` and not `abs(l - pt)`. In the paper, maximum drift is limited to the absolute value of the difference between the logical and physical time as a corollary of the algorithm, which only requires checking when the logical clock is in the future of physical time. This allows us to recv old timestamps, which simplifies clients by allowing them to recv the timestamps of all events before acting and allowing this library to ensure that the causal order is preserved. 2. We were checking max drift on send, but that only catches errors caused by a system administrator setting the system clock to jump or, more commonly, causing an error whenever the computer running the VM sleeps.
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langmartin
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May 28, 2026
NeilMenne
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Relax recv max drift to check only
l - ptand notabs(l - pt). In the paper, maximum drift is limited to the absolute value of the difference between the logical and physical time as a corollary of the algorithm, which only requires checking when the logical clock is in the future of physical time. This allows us to recv old timestamps, which simplifies clients by allowing them to recv the timestamps of all events before acting and allowing this library to ensure that the causal order is preserved.We were checking max drift on send, but that only catches errors caused by a system administrator setting the system clock to jump or, more commonly, causing an error whenever the computer running the VM sleeps.