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Quick Reference: Best Practice Settings

Quick Reference: Best Practice Settings 

This is the quick reference guide to our recommended changes.  If you would like a more in-depth explanation including where these settings reside, please continue to PDF Guide: VMware vSphere Best Practices for the Pure Storage® FlashArray

ESXi Parameters Recommended Default Description

VMware Tools

Install

Not Installed

VMware paravirtual driver, clock sync, increased disk timeouts, and graphic support are part of the tools hence it is crucial step.

HardwareAcceleratedMove

1

1

Enables and controls use of XCOPY on ESXi.

HardwareAcceleratedInit

1

1

Enables and controls use of Block Same AKA WRITESAME

VMFS3.HardwareAcceleratedLocking

1

1

Enables and controls the use of Atomic Test & Set (ATS)

EnableBlockDelete (vSphere 6.x only)

1

0

Disabled by default.  Provides for end-to-end in-guest support for Space Reclamation/UNMAP. Not needed when VMFS-6 is used. Only applicable for VMFS-5.

Path Selection Policy

Round Robin

MRU

Path selection policy for FC and iSCSI.

IO Operations Limit (Path Switching)

1

1000

How many I/Os until ESXi switches to another path for a volume.

TCP Delayed ACK (iSCSI)

Disabled

Enabled 

Improves performance when disabled in congested networks.

iSCSI Login Timeout

30

5

Ensures iSCSI sessions survive controller reboots.

Jumbo Frames (Optional)

 

9000 1500  Change at your discretion.
 Disk.DiskMaxIOSize  4096  32768

Dictates the largest IO the ESXi kernel will transmit. This must be lowered when using EFI-enabled virtual machines, or using VMware vSphere Replication.

 ESXi 5.5 UNMAP Block Count  1% of the free VMFS space or less.  200 Refer to the VAAI or Best Practices document for more information.
VM Virtual SCSI Adapter Paravirtual SCSI Adapter Usually LSI Logic Not required to be changed, but for high-performance requirements, PVSCSI is required to be used.
VMFS version 6 5 Use VMFS-6 when possible (vSphere 6.5 and later).
DSRNO (No. of Outstanding I/Os from competing worlds). 32 32 Default is usually recommended. For high-performance workloads, this might need to be increased.
HBA Queue Depth Limits Default. Varies by vendor. Default is usually recommended. For high-performance workloads, this might need to be increased.