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014-safekeeper-gossip #13
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stepashka
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c/safekeeper
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I'm going to open a new one in zenith repo |
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| ## Proposed implementation | ||
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| Each safekeeper can periodically ping all its peers and share connectivity and liveness info. If the ping was not receiver for, let's say, four ping periods, we may consider sending safekeeper as dead. That would mean some of the alive safekeepers should connect to the pageserver. One way to decide which one exactly: `make_connection = my_node_id == min(alive_nodes)` |
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If a safekeeper fails, isn't that a human intervention scenario anyway? Or do we have a membership change implementation? It's a tricky thing to get right
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Safekeeper gossip
Motivation
In some situations, safekeeper (SK) needs coordination with other SK's that serve the same tenant:
Summary
Compute node has connection strings to each safekeeper. During each compute->safekeeper connection establishment, the compute node should pass down all that connection strings to each safekeeper. With that info, safekeepers may establish Postgres connections to each other and periodically send ping messages with LSN payload.
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