User Manual

SCSI Commands Reference Manual, Rev. J 415
www.seagate.com Parameters for direct access devices
5.3.18 Informational Exceptions Control mode page (1Ch)
The Informational Exceptions Control mode page (see table 390) defines the methods used by the device server to control the
reporting and the operations of specific informational exception conditions. This page shall only apply to informational
exceptions that report an additional sense code of FAILURE PREDICTION THRESHOLD EXCEEDED or an additional sense code of
WARNING to the application client. The mode page policy (see 5.4.14) for this mode page shall be shared, or per I_T nexus.
Informational exception conditions occur as the result of vendor specific events within a logical unit. An informational exception
condition may occur asynchronous to any commands issued by an application client.
PS bit, SPF bit, PAGE CODE field, and PAGE LENGTH field
The PS bit, SPF bit, PAGE CODE field, and PAGE LENGTH field are described in 5.3.5.
PERF (Performance) bit
0 If the performance (PERF) bit is set to zero, informational exception operations that are the cause of delays are acceptable.
1 If the PERF bit is set to one, the device server shall not cause delays while doing informational exception operations. A PERF bit set to
one may cause the device server to disable some or all of the informational exceptions operations, thereby limiting the reporting of
informational exception conditions.
EBF (Enable Background Function) bit
1 If background functions are supported and the Enable Background Function (EBF) bit is set to one, then the device server shall enable
background functions.
0 If the EBF bit is set to zero, the device server shall disable the functions. Background functions with separate enable control bits (e.g.,
background medium scan defined in 4.3.7 are not controlled by this bit.
For the purposes of the EBF bit, background functions are defined as idle time functions that may impact performance that are performed by a
device server operating without errors but do not impact the reliability of the logical unit (e.g., read scan).
Table 390 Informational Exceptions Control mode page
Bit
Byte
7 6 5 4 3 2 1 0
0 PS SPF (0b) PAGE CODE (1Ch)
1 PAGE LENGTH (0Ah)
2 PERF Reserved EBF EWASC DEXCPT TEST EBACKERR LOGERR
3 Reserved MRIE
4 (MSB)
INTERVAL TIMER. . .
7 (LSB)
8 (MSB)
REPORT COUNT. . .
11 (LSB)