BIO
The Batch I/O (BIO) sampler produces a warning message when a batch address space uses more than a specified percentage of the total system I/O activity during a reporting interval.
The message can be suppressed if a given total system I/O rate threshold is not reached during a reporting interval.
Syntax
The parameters are defined as follows:
Parameter | Description |
|---|---|
int | is the length in intervals of the sample period; the default sample period is 30 seconds (one interval) |
percent | is the percentage of total system I/O that a batch address space must be responsible for before an exception message is issued for that address space |
rptno | is the maximum number of batch address spaces to be listed whenever a batch I/O overload condition is detected The maximum value allowed is 10. |
rate | is the number of EXCPs-per-second that must be reached before exception messages are issued; the default is a system I/O rate greater than 25 EXCPs per second |
Example
Assuming a report interval of 30 seconds, the following control statement displays warning messages at two-minute intervals if the system I/O rate exceeds 50 EXCPs-per-second over the preceding two minutes:
BIO 4,25,5,50
A warning is issued for any batch address space doing more than 25 percent of the I/O.
Warning messages
The following warning message is issued by the BIO sampler:
PWSBIO95 *WARNING* I/O RATE FOR JOB nnnnnnnn IS xxx% OF SYSTEM TOTAL
Message PWSBIO95 indicates that the specified address space has exceeded the warning threshold for percentage of system I/O, where
Variable | Description |
|---|---|
nnnnnnnn | is the address space name |
xxx | is the percent of the total system I/O rate |
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