The average amount of time spent on asynchronous reads of data and index pages into a buffer pool. The reads are performed by asynchronous engine dispatchable units ( EDUs ). They are asynchronous in that they occur ahead of requests from agents.
Average asynchronous read time is shown in milliseconds. It provides a measure of the I/O being performed for the tablespaces assigned to a buffer pool. To see elapsed asynchronous read time, check Pool Async Read Time (msec) in the Buffer Pool Details tab.