Specifications

If you are use the Veritas volume manager on the ESS LUNs, you must set
the VxVM max I/O size parameter (vol_maxio) to match the maxphys
parameter. If you set the maxphys parameter to 8388608, add the following
line to the /etc/system file to set the VxVM I/O size to 8 MB:
set vxio:vol_maxio=16384
Emulex or QLogic adapters
Perform the following steps to set the Sun host system parameters for optimum
performance on the ESS with the Emulex or QLogic adapter:
1. Type cd / etc to change to the /etc subdirectory.
2. Backup the system file in the subdirectory.
3. Edit the system file and set the following parameters for servers with
configurations that only use Emulex or QLogic adapters.
sd_io_time
This parameter specifies the time-out value for disk operations. Add the
following line to the /etc/system file to set the sd_io_time parameter for the
ESS LUNs:
set sd:sd_io_time=0x78
sd_retry_count
This parameter specifies the retry count for disk operations. Add the
following line to the /etc/system file to set the sd_retry_count parameter for
the ESS LUNs:
set sd:sd_retry_count=5
maxphys
This parameter specifies the maximum number of bytes you can transfer for
each SCSI transaction. The default value is 12 6976 (124 KB). If the I/O
block size that you requested exceeds the default value, the request is
broken into more than one request. The value should be tuned to the
intended use and application requirements. For maximum bandwidth, set
the maxphys parameter by adding the following line to the /etc/system file:
set maxphys=8388608
If you use Veritas volume manager on the ESS LUNs, you must set the
VxVM max I/O size parameter (vol_maxio) to match the maxphys
parameter. If you set the maxphys parameter to 8388608, add the following
line to the /etc/system file to set the VxVM I/O size to 8 MB:
set vxio:vol_maxio=16384
Chapter 10. Attaching to a Sun host 119