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850d9cfb59
This collector reads nvme temperature sensor, which was observed to cause bad performance on Azure cloud following the reading of the sensor for ~6 seconds. During the event, we can see elevated system time (up to 30%) and softirq time. CPU utilization is high, with nvm_queue_rq taking several orders of magnitude more time than normally. There are signs of contention, we can see __pv_queued_spin_lock_slowpath in the perf profile, called. This manifests as latency spikes and potentially also throughput drop due to reduced CPU capacity. By default, the monitoring stack queries it once every 60s. Closes scylladb/scylladb#21165