Linux diagnose code use
Red Hat® Enterprise Linux® 9.2 issues several diagnose instructions to the hypervisor (LPAR, z/VM®, or KVM).
Read /sys/kernel/debug/diag_stat to find out which diagnose instructions are
called how frequently on your Linux
instance.
# cat /sys/kernel/debug/diag_stat
CPU0 CPU1
diag 008: 7 7 Console Function
diag 00c: 0 0 Pseudo Timer
diag 010: 0 0 Release Pages
diag 014: 0 0 Spool File Services
diag 044: 7 5 Voluntary Timeslice End
diag 064: 0 0 NSS Manipulation
diag 09c: 53 92 Relinquish Timeslice
diag 0dc: 0 0 Appldata Control
diag 204: 2 0 Logical-CPU Utilization
diag 210: 3 6 Device Information
diag 224: 0 0 EBCDIC-Name Table
diag 250: 0 0 Block I/O
diag 258: 1 1 Page-Reference Services
diag 26c: 2 0 Certain System Information
diag 288: 0 0 Time Bomb
diag 2c4: 0 0 FTP Services
diag 2fc: 2 0 Guest Performance Data
diag 304: 0 0 Partition-Resource Service
diag 308: 1 1 List-Directed IPL
diag 318: 1 1 CP Name and Version Codes
diag 500: 0 0 Virtio ServiceThe z/VM configuration can modify and restrict the diagnose calls that are available to its guests.