> However, unlike the log-based approach, this does not ensure monotonicity across multiple concurrent requests.
Is this a functional requirement when a system is multi-process? Specifically, a single multi-threaded process could provide monotonic guarantees across all messages processed.
Once 2+ processes are introduced, it is impossible to guarantee monotonicity globally unless a SPoT (a.k.a. "queue") is used for delivery due to variations in message delivery times, performance of machines running each process, etc. An additional implication is there is no provable way to determine if a message received by process "A" logically precedes a message received by process "B" without authoritative information in the messages.
In short, an answer which generalizes the question:
Can we get the space efficiency for consumers when using
monotonically increasing idempotency keys, without
hampering performance of multi-threaded producers?
Is to use the "hi/low" algorithm for both a single process multi-threaded solution, by only needing the process to allocate the "hi" value periodically and provide verifiable monotonic values, and also for multi-process (potentially multi-threaded as well) solutions, which ensures each process does not produce duplicate keys while providing a per-process partial ordering guarantee.
Is this a functional requirement when a system is multi-process? Specifically, a single multi-threaded process could provide monotonic guarantees across all messages processed.
Once 2+ processes are introduced, it is impossible to guarantee monotonicity globally unless a SPoT (a.k.a. "queue") is used for delivery due to variations in message delivery times, performance of machines running each process, etc. An additional implication is there is no provable way to determine if a message received by process "A" logically precedes a message received by process "B" without authoritative information in the messages.
In short, an answer which generalizes the question:
Is to use the "hi/low" algorithm for both a single process multi-threaded solution, by only needing the process to allocate the "hi" value periodically and provide verifiable monotonic values, and also for multi-process (potentially multi-threaded as well) solutions, which ensures each process does not produce duplicate keys while providing a per-process partial ordering guarantee.