Make PercentileSpeculativeExecutionPolicy.percentile cluster wide

Description

Current percentile is per host so if a specific host is functional but sick it will have long latencies. In such cases, the request is sent to a different co-ordinator after long time.

It is better to use a cluster wide percentile instead of being at the mercy of specific host.


Resolution:
Extracted an abstract PercentileTracker, and added a new ClusterWidePercentileTracker implementation.

Environment

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Pull Requests

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Status

Assignee

Olivier Michallat

Reporter

Vishy Kasar

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Sprint

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Major
Configure