high percentage on 'iowait'
Posted on 2014-03-05
I got the problem on the 'root' partition of the Linux RHEL3 server which is suddenly having the partition become read only. The case solve by rebooting the server.
On checking the 'top' status, it is found that an abnormal behavior is having the 'iowait' persist at a high rate and at the time of the incident, the 'iowait' always reaches 90-100 %
Will this be the cause of the partition becoming read only ?
If it is, what is the possible reason of the 'iowait' becoming high ?
Last but most important, how to solve this issue ?
Below showing that the iowait reaches 100% this morning and then the partition cannot write again.
03:44:02 up 7:02, 0 users, load average: 0.00, 0.00, 0.00
62 processes: 61 sleeping, 1 running, 0 zombie, 0 stopped
CPU states: cpu user nice system irq softirq iowait idle
total 0.0% 0.0% 0.0% 0.0% 0.0% 100.0% 0.0%
Mem: 2056864k av, 175268k used, 1881596k free, 0k shrd, 67172k buff
111756k active, 25436k inactive
Swap: 4192956k av, 0k used, 4192956k free 66368k cached