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07eec357ee
It was a bit of an overreach to try and limit duplicate request processing in the network layer. It introduced acks and the necessity to resync last_processed_id on reconnect. In testing compaction requests we saw that request processing stopped if a client reconnected to a new server. The new server sent low request ids which the client dropped because they were lower than the ids it got from the last server. To fix this we'd need to add smarts to reset ids when connecting to new servers but not existing servers. In thinking about this, though, there's a bigger problem. Duplicate request processing protection only works up in memory in the networking connections. If the server makes persistent changes, then crashes, the client will resend the request to the new server. It will need to discover that the persistent changes have already been made. So while we protected duplicate network request processing between nodes that reconnected, we didn't protect duplicate persistent side-effects of request processing when reconnecting to a new server. Once you see that the request implementations have to take this into account then duplicate request delivery becomes a simpler instance of this same case and will be taken care of already. There's no need to implement the complexity of protecting duplicate delivery between running nodes. This removes the last_processed_id on the server. It removes resending of responses and acks. Now that ids can be processed out of order we remove the special known ID of greeting commands. They can be processed as usual. When there's only request and response packets we can differentiate them with a flag instead of a u8 message type. Signed-off-by: Zach Brown <zab@versity.com>