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intr_priority
daemon
host_address
scat_gat_pages
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dma_mem
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poll_threshold
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Device-Dependent Subroutines
The SSA adapter device driver provides support only for the open, close, and ioctl
subroutines. It does not provide support for the read and write subroutines.
open and close Subroutines
The open and openx subroutines must be called by any application program that wants
to send ioctl calls to the device driver.
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User's Guide and Maintenance Information
Holds the value of the interrupt priority that the SSA adapter device driver for
this adapter will use.
Specifies whether to start the SSA adapter daemon. If the attribute is set to
TRUE, the daemon is started when the adapter is configured.
The daemon holds the adapter device driver open although the operating
system might not be using that adapter device driver at the time. This action
allows the adapter device driver to reset the adapter card if the software that is
running on it finds an unrecoverable problem. It also allows the adapter device
driver to log errors against the adapter.
The ability of the device driver to log errors against the adapter is especially
useful if the adapter is in an SSA loop that is used by another adapter,
because failure of this adapter can affect the availability of the SSA loop to the
other adapter.
You can use the chdev command to change the value of this attribute.
Holds the host address (using-system address) for this adapter.
Specifies the number of 4-kilobyte pages that the device driver has kept for the
management of scatter/gather lists. If many large transfer operations are to be
performed, think about increasing the value of this attribute if the I/O does not
reach the expected rate.
Specifies the size of the DMA memory. On systems that are using AIX version
4.3 or above, the memory should be big enough to hold the biggest expected
I/O load. If you specify too small a size, the system cannot reach the
best-possible I/O rate.
Specifies how many command completions must occur in a 10 millisecond
period to cause the adapter device driver to switch so that it is driven by
polling-command completions rather than by interrupts. Polling might reduce
the load on the system processor, but it can also cause longer I/O response
times.
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