> Spanner is consistent, available and partition tolerant due to the extremely precise clock synchronization...
This is nonsensical; even in a universe without relativity and with instantaneous communication--an unrealistic world where being able to talk about synchronized clocks can even make sense (as otherwise you fundamentally must deal with an inability to decide the order of two events due to latency)--you still cause indeterminate simultaneity by introducing a partition: your perfectly accurate and infinitely precise timestamps on one side of the partition would no longer be comparable with timestamps on the other side of the partition for purposes of establishing causality between events, as the recent changes being made on one side of the partition "should have" taken place between any older changes on the other side and any transactions being performed right now, and yet they couldn't because they were unknown. Spammer either gives up availability (waiting to verify what happened) or consistency (accepting that it will have to fix the result later) when a partition occurs: they can't do both, fundamentally; the only extent to which there is an engineering challenge here is "maybe you can minimize the number of partitions you have", which I totally believe Google to have done; but, given a partition (which cannot be fully prevented), the tradeoff is clear and unavoidable.
This is nonsensical; even in a universe without relativity and with instantaneous communication--an unrealistic world where being able to talk about synchronized clocks can even make sense (as otherwise you fundamentally must deal with an inability to decide the order of two events due to latency)--you still cause indeterminate simultaneity by introducing a partition: your perfectly accurate and infinitely precise timestamps on one side of the partition would no longer be comparable with timestamps on the other side of the partition for purposes of establishing causality between events, as the recent changes being made on one side of the partition "should have" taken place between any older changes on the other side and any transactions being performed right now, and yet they couldn't because they were unknown. Spammer either gives up availability (waiting to verify what happened) or consistency (accepting that it will have to fix the result later) when a partition occurs: they can't do both, fundamentally; the only extent to which there is an engineering challenge here is "maybe you can minimize the number of partitions you have", which I totally believe Google to have done; but, given a partition (which cannot be fully prevented), the tradeoff is clear and unavoidable.