use current node load estimation when placing search jobs#6390
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trinity-1686a wants to merge 8 commits into
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use current node load estimation when placing search jobs#6390trinity-1686a wants to merge 8 commits into
trinity-1686a wants to merge 8 commits into
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May 7, 2026
| fn compute_split_cost(split_metadata: &SplitMetadata) -> usize { | ||
| pub(crate) fn compute_split_cost(num_docs: u64) -> usize { | ||
| // TODO this formula could be tuned a lot more. The general idea is that there is a fixed | ||
| // cost to searching a split, plus a somewhat-linear cost depending on the size of the split |
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this should include if we have aggregations or not, or ideally a cost from the query
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May 11, 2026
| // Seed each candidate node with its current load so the placer avoids | ||
| // routing work to already-loaded nodes. If a node fails to report its | ||
| // load (error or timeout), `load` stays `None`: we still route work | ||
| // there if all other nodes are overloaded, but we prefer reachable |
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maybe we should error instead if all nodes are not reachable or overloaded
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When placing jobs, first query all nodes for their current load, and bias placement toward less loaded nodes to even load on the cluster
this improves on a problem where some nodes might be overloaded while other are underloaded, causing queueing despite not all nodes being at max capacity
in testing, this was seen improving slightly p50+ under constant light load, and increased the max qps before latency explodes. Metrics also showed all searcher busy when some would be only part-time working before
future improvements: