Improving z/OS I/O Resiliency

A recent health check for I/O was added that allows you to monitor for command response time disparities among paths in a path group.  This allows you to be more pro-active in determining the root cause of elongated response times when one or more paths to your I/O devices are not in line time-wise with the others in the group. 

A second topic covered here is an improvement in z/OS V1R13 that provides I/O path recovery scoped at the control unit level.  When path related I/O error occurs on paths in a control unit, the I/O supervisor will monitor for trends and take action to remove paths for all devices associated with the control unit when the number of path-related errors exceeds specified thresholds.

Tracks: Storage and z/OS Systems Programming