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CockroachDB — the cloud native, distributed SQL database designed for high availability, effortless scale, and control over data placement.
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kvserver: smear size based range splits #125929

Open kvoli opened 2 months ago

kvoli commented 2 months ago

When running a uniform write workload, on a uniformly sized keyspace, ranges will split in half at approximately the same time.

Normally, when a few ranges split this isn't expected to have any impact as https://github.com/cockroachdb/cockroach/issues/22348 removes the latch contention latency. However, scanning the range data simultaneously for many splits can cause CPU exhaustion, which does result in higher tail latency.

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This issue is to smear, or space out size-based range splits so that they do not all occur at the same time for uniform workloads.

Jira issue: CRDB-39670

Epic CRDB-39952

blathers-crl[bot] commented 2 months ago

Hi @kvoli, please add branch-* labels to identify which branch(es) this C-bug affects.

:owl: Hoot! I am a Blathers, a bot for CockroachDB. My owner is dev-inf.