RTM-ATCA-SXXX Overview
6806800H62B ATCA‐S201InstallationandUseGuide87
Note: The <value> should be set to multiples of PAGE_SIZE. The maximum supported value is 64 * 4096 =
262144.
#FirstBurstLength <value>
Default: 65536, Sets the maximum amount of unsolicited data the initiator may transmit in the first burst of a
transfer either with and/or right after the iSCSI command. Used together with InitialR2T and ImmediateData.
Note: The <value> should be set to multiples of PAGE_SIZE. The maximum supported value is 16 * 4096 =
65536.
#DefaultTime2Wait<value>
Not currently supported
#DefaultTime2Retain <value>
Not currently supported
#MaxOutstandingR2T <value>
Default: 1, Controls the maximum number of data transfers the target may request at once, each of up to
MaxBurstLength bytes.
#DataPDUInOrder <Yes|No>
"Yes" — default:, Indicates the initiator MUST send data PDUs within sequences have to be at continuously
increasing addresses.
“No” — Not supported.
#DataSequenceInOrder <Yes|No>
"Yes" — default: Indicates the initiator MUST send Data Sequences with continuous non-decreasing sequence
offsets (R2T buffer offset for writes, or the smallest SCSI Data-In buffer offset within a read data sequence).
“No” — Not supported.
#ErrorRecoveryLevel 0
Default 0, Establishes the recovery level supported by the target.
#HeaderDigest <CRC32C|None>
"None" — default. CRC not enabled.
"CRC32C" — Indicates Target will support CRC32C checksum to protect iSCSI PDU’s headers, if requested by
initiator.
Notes: (1) header digests are not used during discovery sessions. (2) CRC32C may negatively affect overall target
performance.
#DataDigest <CRC32C|None>
"None" — default. CRC not enabled.
"CRC32C" — Indicates Target will support CRC32C checksum to protect iSCSI PDU’s data segments, if requested
by initiator.
Notes: (1) data digests are not used during discovery sessions. (2) CRC32C may negatively affect overall target
performance.
#Wthreads <value>
Default: 8
Sets the number of threads used to perform the block I/O to the blades’ disk resources. 8 threads was
determined optimal for the majority of deployments and workloads.
Lun <number> Path=<device>,Type<blockio>,ScsiID=<unique-identifier>
defines a mapping between a Logical Unit Number <number> and a block device <device>.
<number>: The value between 0 and 2^14-1
<device>: Linux device path mapped to the LUN
<blockio> Indicates the blade will perform direct block i/o with the device, bypassing page-cache for all
operations. Optimal for non-aligned sector transfers large block transfers.
<unique-identifier> a unique ID assigned to the iSCSI volume. It is required to assist mulitipath-aware initiator
host accessing the same <device> through several targets. The <unique-identifier> must not exceed 16
characters.
