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The 5 missing metrics (rchar, wchar, syscr, syscw, and cancelled_write_bytes) are essential for diagnosing performance issues and optimising Kafka deployments as without these metrics, operators cannot calculate cache hit ratios to understand page cache effectiveness (rchar vs read_bytes), detect write amplification from filesystem overhead (write_bytes vs wchar), identify inefficient I/O patterns from excessive system calls, or monitor log compaction activity. These blind spots make troubleshooting significantly harder. 
 
The proposed change exposes all 7 metrics via JMX with zero low overhead as the data is already being read from the kernel, we are simply parsing and exposing the 5 additional fields that are currently discarded. 

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