This section contains
information as seen by the Access Method Services component of z/OS.
Notes:
- All delay values are in units of 128 microseconds.
- The I/O delay is only calculated by Access Method Services when the application checks whether an I/O buffer is available to be reused (for example, when an access method has issued an I/O request to commit the buffer). The timer starts when the caller makes the check request; it does not start when the I/O is requested. The timer ends when the I/O request completes. Thus, the delay value that is reported is the amount of time that the caller had to wait to reuse a buffer.
| Offsets | Name | Length | Format | Description | |
|---|---|---|---|---|---|
| 0 | 0 | S42AMSRB | 4 | binary | Sequential read: number of blocks |
| 4 | 4 | S42AMSRR | 4 | binary | Sequential read: I/O delay |
| 8 | 8 | S42AMSWB | 4 | binary | Sequential write: number of blocks |
| 12 | 0C | S42AMSWR | 4 | binary | Sequential write: I/O delay |
| 16 | 10 | S42AMDRB | 4 | binary | Direct read: number of blocks |
| 20 | 14 | S42AMDRR | 4 | binary | Direct read: total I/O delay |
| 24 | 18 | S42AMDWB | 4 | binary | Direct write: number of blocks |
| 28 | 1C | S42AMDWR | 4 | binary | Direct write: total I/O delay |
| 32 | 20 | S42AMZRB | 4 | binary | Number of directory reads |
| 36 | 24 | S42AMZRR | 4 | binary | Directory read: I/O delay |
| 40 | 28 | S42AMZWB | 4 | binary | Number of directory writes |
| 44 | 2C | S42AMZWR | 4 | binary | Directory write: I/O delay |