Host queue depth

Open-Systems Host Attachment Guide for Virtual Storage Platform Family

Version
A3-04-2x
10.4.x
Audience
anonymous
Part Number
MK-90RD7037-35
ft:lastEdition
2025-09-02

You can adjust the queue depth settings as needed to optimize the I/O performance of the devices. The appropriate queue depth settings (max tag count) for each operational environment must be carefully researched and determined. In addition, the requirements for host queue depth depend on the storage system model.

The following table lists the queue depth settings to ensure smooth processing at the ports and best average performance. Other queue depth settings, higher or lower than these values, can provide improved performance for certain workload conditions.

CAUTION:
Higher queue depth settings (for example, >2,048 per port) can impact host response times. Exercise caution when using queue depth settings that are higher than these values.

Queue depth settings

Storage system Best practice queue depth settings
VSP One Block 20 Bidirectional ports (Target and Initiator):
  • 1,024 Target function
  • 1,024 Initiator function
  • 32 per LDEV
VSP 5000 series Target ports:
  • 2,048 per port
  • 32 per LDEV

Bidirectional ports (Target and Initiator):

  • 1,024 Target function
  • 1,024 Initiator function
  • 32 per LDEV
VSP G1x00, VSP F1500
  • 2,048 per port
  • 32 per LDEV
VSP E series Bidirectional ports (Target and Initiator):
  • 1,024 Target function
  • 1,024 Initiator function
  • 32 per LDEV
VSP G130, G/F350, G/F370, G/F700, G/F900 Bidirectional ports (Target and Initiator):
  • 1,024 Target function
  • 1,024 Initiator function
  • 32 per LDEV
VSP G200, G400, G600, G800, VSP F400, F600, F800
  • 1,024 per port
  • 32 per LDEV