The graph below shows an example of the I/O operations when an I/O response delay occurs on a disk with the I/O response time set to 23 seconds.
The I/O returns in a maximum time of 23 seconds to the application even if the I/O response of the other disk (disk 2 in this example) is delayed. (After this, the I/O of disk 2 returns.)
GDS: Global Disk Services