Implementation of jump consistent hashing for selecting servers #110
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This change adds new logic for selecting which server owns a particular key based on the jump consistent hash. This logic is much faster than the existing rendezvous hashing but is more operationally fragile. Using jump consistent hashing requires that servers are always in the same order and that servers are added and removed from the end of this list, think how statefulsets in Kubernetes work. It's not currently possible to make use of this in mtop since we have no way to look up the names of servers until we add support for SRV DNS records. Until then, servers are ordered by their SocketAddr which means they would end up being removed from the middle of the list which completely breaks jump consistent hashing. Depends on #107
56quarters
added
enhancement
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Closing since jump hashing isn't needed for |
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This change adds new logic for selecting which server owns a particular key based on the jump consistent hash. This logic is much faster than the existing rendezvous hashing but is more operationally fragile.
Using jump consistent hashing requires that servers are always in the same order and that servers are added and removed from the end of this list, think how statefulsets in Kubernetes work.
It's not currently possible to make use of this in mtop since we have no way to look up the names of servers until we add support for SRV DNS records. Until then, servers are ordered by their SocketAddr which means they would end up being removed from the middle of the list which completely breaks jump consistent hashing.
Depends on #107