iostat

• iostat.1Linkman7.org/linux/man-pages/man1/iostat.1.htmliostat.1 · | column | · | %user | CPU usage at the normal user level | · | %nice | CPU usage at the user level with priorities |笔记：iostat

iostat -d -x 1
iostat -cdxy 2

| column | | -------- | -------------------------------------------------------------------------------------------------------- | | %user | CPU usage at the normal user level | | %nice | CPU usage at the user level with priorities | | %system | CPU utilization that occurred while executing at the system level (kernel) | | %iowait | CPUs were idle and the system received I/O requests | | %steal | involuntary wait by the virtual CPU or CPUs while the hypervisor was servicing another virtual processor | | %idle | CPU or CPUs were idle and the system did not have an outstanding disk I/O request | | tps | r/s+w/s+d/s+f/s | | r/s | read/second | | w/s | write/second | | d/s | discard/second | | f/s | flush/second | | %rrqm | read requests merged | | %util | Percentage of elapsed time during which I/O requests were issued to the device | | avgqu-sz | | svctm | average amount of time an operation takes |

• 串行和并行 存储设备参考逻辑上有差异
• 并行设备无参考价值的信息: svctm, %util
• 参考
  • Two traps in iostat: %util and svctm