Parameters for improving performance for 25-Gbps iSCSI

Provisioning Guide for VSP One Block

Version
10.2.x
Audience
anonymous
Part Number
MK-23VSP1B012-00

If using a 25-Gbps iSCSI channel board does not achieve the level of I/O performance you expected, performance might improve by configuring the following parameters in hosts.

When you configure the parameters, the set values are applied to I/O of all devices that are connected to your host. If the host is connected to devices other than a 25-Gbps iSCSI channel board, make sure that the new values of the parameters do not affect I/O of other devices before you set the values.

If you run a virtual machine on VMware ESXi, configure the parameters in the OS of the virtual machine.

Parameter Value to be set
MTU 9000
Socket buffer size

The value to be set differs depending on the OS of your host.

  • For Windows Server 2019/2022: normal
  • For Red Hat Enterprise Linux: 3145728 or greater
  • For SUSE Linux: 3145728 or greater
  • When using VMware ESXi as the iSCSI initiator: No specification is required.
Immediate data

The value to be set differs depending on the OS of your host.

  • For Windows Server 2019/2022: 0x00000001 (ON)
  • For Red Hat Enterprise Linux: Yes
  • For SUSE Linux: Yes
  • When using VMware ESXi as the iSCSI initiator: true
Maximum receive data segment length 262144 or greater
First burst length 262144 or greater
Maximum burst length 262144 or greater
Header digest

The value to be set differs depending on the OS of your host.

  • For Windows Server 2019/2022:CRC32
  • For Red Hat Enterprise Linux: None
  • For SUSE Linux: None
  • When using VMware ESXi as the iSCSI initiator: Prohibited
Data digest

The value to be set differs depending on the OS of your host.

  • For Windows Server 2019/2022: CRC32
  • For Red Hat Enterprise Linux: No specification is required.
  • For SUSE Linux: No specification is required.
  • When using VMware ESXi as the iSCSI initiator: Prohibited