"performance has improved" messages in ESXi logs

Products

• VMware vSphere ESXi

Issue/Introduction

You receive this message when the storage device performance improves. This event is generated as the device latency decreases. This occurs when either the latency ratio to the last time the log was updated is 5 or it doubles.

 

The following is an example of the message received in vmkernel.log when this occurs:

Device naa.5000c5000b36354b performance has improved. I/O latency reduced from 19403 microseconds to 1201 microseconds.

Environment

VMware vSphere ESXi 8.x

VMware vSphere ESXi 7.x

VMware vSphere ESXi 6.x

Resolution

No solution is necessary. This is an information-only event.

Additional Information

For more/related information, see:

• Storage device performance deteriorated (2007236)

For translated versions of this article, see:

• 日本語: ストレージ デバイスのパフォーマンスの改善 (2102278)