System IO Monitoring
Iostat Monitoring of individual disk usage
- RRQM/S: The number of read operations per second for the merge. That is Delta (rmerge)/s
- WRQM/S: The number of write operations per second for the merge. That is, Delta (wmerge)/s
- R/S: Number of Read I/O devices completed per second. Delta (RIO)/s
- W/S: Number of write I/O devices completed per second. Delta (WIO)/s
- RSEC/S: Number of Read sectors per second. Delta (rsect)/s
- WSEC/S: Number of Write sectors per second. Delta (wsect)/s
- rkb/s: Read K bytes per second. Is half of the rsect/s because the size of each sector is 512 bytes. (Calculation required)
- wkb/s: Writes K bytes per second. It's half the wsect/s. (Calculation required)
- AVGRQ-SZ: The data size (sector) of the average Per device I/O operation. Delta (Rsect+wsect)/delta (Rio+wio)
- Avgqu-sz: Average I/O queue length. That is Delta (AVEQ)/s/1000 (because Aveq is in milliseconds).
- Await: The average wait time (in milliseconds) for each device I/O operation. Delta (Ruse+wuse)/delta (Rio+wio)
- SVCTM: The average service time (in milliseconds) per device I/O operation. Delta (use)/delta (RIO+WIO)
- %util: CPU usage time per second for IO operations. That is, the amount of time in a second for I/O operations, or how much time in a second I/O queue is non-empty, calculation method: (r/s+w/s) * (svctm/1000)
%util indicates how busy the disk is. 100% indicates that the disk is busy and 0% indicates that the disk is idle. Note, however, that disk busy does not represent high disk (bandwidth) utilization
Can only reflect the system disk is busy, cannot indicate that process is busy.
Process IO Monitoring
- TID: thread or Process ID
- PRIO: Thread IO Priority
- User: Thread-owned users
- Disk read: The speed at which the thread reads data from the disks
- Disk write: The speed at which thread writes to disk
- Swapin: The percentage of total process IO time that the data used by the process is swapped into memory by the swap
- IO: The percentage of the total process IO time that the process waits for IO operations
Business level IO monitoring ioprofile full file level IO monitoring
LOSF: "List open Files" (list opened file)
From your own native view Nginx master process opened those files
viewing nginx log information
Reference:
Http://www.ibm.com/developerworks/cn/aix/library/au-lsof.html
Http://www.cnblogs.com/quixotic/p/3258730.html
Operating system performance Monitoring-disk IO
