HdrReservoir: add hint to record error on how to fix it#602
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dkropachev merged 1 commit intoscylladb:scylla-4.xfrom Sep 13, 2025
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When HdrHistogram writes latency if latency is higher than maximum expected it throws error. Driver catches this error and logs it. Users get confused since there is no reciepe how to fix it. Solution is to set advanced.metrics.session.cql-requests.highest-latency to maximum possible latency, which is request timeout. But since request timeout could be configured on the execution profile, we can't automatically tune highest-latency to match it. So, only good solution is to give user a hint in the log message.
Bouncheck
approved these changes
Sep 12, 2025
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When HdrHistogram writes latency if latency is higher than maximum expected it throws error.
Driver catches this error and logs it.
Users get confused since there is no reciepe how to fix it.
Solution is to set
advanced.metrics.session.cql-requests.highest-latencyto maximum possible latency, which is request timeout.But since request timeout could be configured on the execution profile, we can't automatically tune highest-latency to match it.
So, only good solution is to give user a hint in the log message.