Performance Tuning - Chelsio T5 Installation And User Manual

Chapter 5. Software/Driver Configuration and Fine-tuning
5.11.3. iscsi_target_vendor_id
Options: A string of maximum of 8 characters, defaults to
The iscsi_target_vendor_id
response of a SCSI Inquiry request.
5.11.4. iscsi_chelsio_ini_idstr
Options: A string of maximum of 255 characters, defaults to "cxgb4i".
For an iscsi connection, more optimization can be done when both initiator and target are
running Chelsio adapters and drivers.
This string is used to verify the initiator name received, and identify if the initiator is running
Chelsio drivers: if the initiator name contains the same substring as
it is assumed the initiator is running with the Chelsio iscsi initiator driver and additional offload
optimization is performed.
5.12.

Performance Tuning

In order to auto tune the system for best performance, Chelsio recommends:

Disabling virtualization, c-state technology, VT-d, Intel I/O AT and SR-IOV in the BIOS
settings.

Installing the adapter into a PCIe Gen3 x8/x16 slot.

Disable SELinux and firewall.

Installing the driver package will copy
script to map the adapter queues to different CPUs:
[root@host~]# t4_perftune.sh
Also, follow the steps mentioned below to lower your latency:
i. If not already done, load the iSCSI target driver.
ii. Run the following script to disable few services.
[root@host~]# t4_latencytune.sh <interface>
iii. Set sysctl param net.ipv4.tcp_low_latency to 1
[root@host~]# sysctl -w net.ipv4.tcp_low_latency=1
Chelsio T5 iSCSI PDU Offload Target with SCST support for Linux
is part of the device identification sent by an iSCSI target in
t4_perftune.sh
CHISCSI
iscsi_chelsio_ini_idstr
script to /sbin directory. Run the
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