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The only "easy" way around these two challenges is to focus our efforts on queries that are restricted to either partitions or small token ranges. These queries behave well locally even on LCS (given levels contain token-disjoint SSTables, and assuming a low number of unleveled SSTables), avoid fan-out and all of its secondary pitfalls, and allow us to make queries at varying CLs with reasonable performance. Attempting to fix the local problems around compaction strategy could mean either restricted strategy usage or partially abandoning SSTable-attachment. Attempting to fix distributed read path problems by pushing the design towards IR systems like ES could compromise our ability to use higher read CLs.

Addendum

Index Format Version 1

The following applies to the version 1 index format.. There is a version 2 index format under development.

JMX metrics

Users will have access to extensive JMX metrics to help them isolate performance issues on their clusters.

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