Advantech PCA-6157, Руководство пользователя

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Chapter 5 SCSI Drive Installation 99
This parameter may be used to optimize the use of dynamically
allocated memory by the driver. If all the host adapters, including
any SCSI controllers on the motherboard are connected to less
than 31 devices, a user can reduce the size of the dynamically
allocated memory by setting this value to the maximum number of
devices on any of the SCSI controllers.
Using the Maximum LUNs Option
Command line option: max_lun=<option>
Default value: 4
Valid options: 1-4
Function: Specify the maximum number of LUNs
each host adapter board should support
per SCSI id.
Possible Impact: If number is reduced, may allow for
reduction in memory used by the driver.
Applicable Versions: 3.04.00 and higher
This parameter may be used to optimize the use of dynamically
allocated memory the driver. If less than 8 LUNs are being used
per NCR based PCI host adapter SCSI id, this parameter will allow
for a reduction in the total memory being used for the driver.
Important additional information
Memory Allocation
The driver allocates memory for certain structures based upon the
maximum number of SCSI IDs (max_id), LUNs (max_lun), and
paths (max_hbas) that may be used in the system. The amount of
memory allocated is based on the following formula:
319 bytes of memory are allocated for the structure, so:
Memory Allocated = 319 x max_hbas x max_lun x max_id.
So for default allocations, the amount of memory allocated is:
Memory Allocated = 319 x 8 x 4 x 32 = 326,656 bytes (400 KB).