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Brocade Adapters Troubleshooting Guide
53-1001582-01
Tuning storage drivers
4
Solaris tuning
To increase I/O transfer performance, set the following parameters on your system:
•
Set the maximum device read/write directive (maxphy).
•
Set the disk maximum transfer parameter (ssd_max_xfer_size).
Please refer to the
Sun StorageTek SAM File System Configuration and Administration Guide
document for details of the two parameters.”
To increase I/O write performance, set the pcie-max-read-reqsz parameter on your system. This
parameter is defined in /kernel/drv/bfa.conf. It determines the maximum read through PCIe. The
default value is 512. To increase performance, you can increase the value to 256, 1024, or 2048. T
NOTE
Brocade mezzanine or expansion card adapters are not supported on Solaris systems.
Windows tuning
Windows tuning involves configuring the driver and operating system tunable parameters.
Driver tunable parameters
You can manipulate several driver parameters to increase performance.
bfa_lun_queue_depth (outstanding I/O requests per LUN)
The driver uses a default LUN queue depth value of 32. This value is chosen to reflect the average
operating I/O load in most scenarios. Storport manages the I/O throttling at the per-LUN level to
guarantee the configured queue depth. During performance testing with specific high-end array
LUNs, it may be necessary to increase this I/O queue depth to a much larger value. Microsoft
recommends a value of 96 during high-performance testing scenarios. If the queue depth is not
sufficient, then you will notice performance degradation.
The queue depth can be configured at the following registry location with any value within the
range 1 through 254.
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\bfad\Parameters\Device\bfa_lun_
queue_depth
Interrupt moderation using interrupt coalescing feature
Moderating interrupts can often result in reduced CPU load on the host but, unless interrupt
moderation is performed intelligently, the CPU savings might increase latency.
The default values for the Fibre Channel port interrupt attributes are configured as follows:
•
Interrupt delay
Default:
-
1125 microseconds on the Brocade 415, 425, 815 and 825
-
25 microseconds on the Brocade
804
, 1010 and 1020
Valid Range: 0 through 1125 microseconds
Note that the value of 0 disables the delay timeout interrupt.
