How to find out and configure the MAX_IO_SIZE in solaris?

The “maxphys” kernel parameter limits the max. I/O size in the SCSI

layer.
Default is 128k.
The “vol_maxio” kernel parameter limits the max. I/O size in the VxVM layer
(if installed). Default is 256k.
The “md_maxphys” kernel parameter limits the max. I/O size in the
DiskSuite/SVM layer (if installed). Default is equal to maxphys.
The “sd_max_xfer_size” module parameter limits the max. I/O size in the SD
module (if installed). Default is 1 Mb.
The ” sd_max_xfer_size” module parameter limits the max. I/O size in the SSD
module (if installed). Default is 1 Mb.

Set the default max. I/O size in Veritas to match/exceed the max. I/O size
that will be used.

in /etc/system, place

set maxphys=1048576
set vxio:vol_maxio=2048
* to allow 1MB I/Os.

vol_maxio is in Veritas units i.e. disk sectors of 512 bytes.
maxphys is in bytes.

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