VM guests experiencing storage latency

Products

• VMware vSphere ESXi

Issue/Introduction

Several guests in the environment were experiencing storage latency

Environment

ESXi 8.0 P07

Cause

vmkernel.log on the hosts where the affected guests reside had entries like the following:

YYYY-MM-DDT17:32:57.966Z Wa(180) vmkwarning: cpu70:2099398)WARNING: NFS: 5927: NFS volume <datastorename> performance has deteriorated. I/O latency increased from average value of 6023(us) to 689442(us).
YYYY-MM-DDT17:32:57.966Z Wa(180) vmkwarning: cpu70:2099398)WARNING: NFS: 5927: NFS volume <datastorename> performance has deteriorated. I/O latency increased from average value of 6023(us) to 1397147(us).

Note the values above are greater than the 20ms threshold for legacy storage and WILL negatively impact guest performance

Resolution

Migrated guests to an SSD-backed datastore and performance improved

Additional Information

仮想マシン上のゲスト OS でストレージ遅延が発生する