Skip to main content

Virtual machines might experience slow performance in vSAN 6.5 while running certain NVMe drivers

  Symptoms

  •  In rare occasions, under high input/output processing conditions you may observe the vSAN disk group going offline.
  • In the /var/log/vmkernel file, you see message similar to:
2020-03-30T15:48:43.044Z cpu7:21644947)nvme:scsiIoCompleteCommand:459:vmkCmd 0x43a194105f00[28h I:0x4307df218480 SN:0x168418e0] UNDERRUN 8192/32768

Note: The preceding log excerpts are only examples. Date, time, and environmental variables may vary depending on your environment.
Cause

This issue is caused in the inbox driver.

Note:This is only observed when using the following NVMe devices in vSAN cluster:

  • Intel NVMe P4800X
  • Intel NVMe P4600/P4500
  • Intel NVMe P4610/ P4510 
Resolution
This issue is resolved in VMware ESXi 6.5 EP20 Patch Release ESXi650-202006001, available at VMware Patch Downloads.
For more information on downloading patch, see How to download patches in MyVMWare (1021623).

Comments

Popular posts from this blog

Increasing the disk space for the VMware vCenter Server Appliance in vSphere 6.5, 6.7 and 7.0

  Purpose This article provides steps to increase the disk space of a specific VMDK for the vCenter Server Appliance 6.5, 6.7 and 7.0. With the introduction of Logical Volume Management (LVM) in vSphere 6.0 and continued support with vSphere 6.5, 6.7 and 7.0, the vCenter Server disks can be dynamically increased. List of VMDKs for a vCenter Server Appliance 6.5 - Size Mount point and Purpose Note : Resizing the root partition (VMDK1 listed in the KB above) is not supported on 6.5. Please see the vSphere 6.5 Release Notes for more information. Resizing root partition has been added to 6.7 and 7.0. List of VMDKs/Partitions for a vCenter Server Appliance 6.7 - Size Mount point and Purpose   List of VMDKs/Partitions for a vCenter Server 7.0 - Size Mount point and Purpose Note : This KB can be used for the situation like SEAT partition full or any other vCenter appliance partition full. ...

Cloning and converting virtual machine disks with vmkfstools

 Purpose This article provides information and instructions on the use of the vmkfstools command to convert virtual machine disks from one type to another. Resolution The vmkfstools command offers the ability to clone virtual machine content and also convert from one virtual machine disk ( .vmdk ) format into another. Note : The host operating system chosen to perform the conversion may not necessarily support running of virtual machines via the output format defined. vmkfstools maintains the possibility of exporting virtual disks for use in other VMware products which support alternative disk formats. To convert a virtual machine disk from one type to another: Shut down the virtual machine. Virtual machine disk files are locked while in-use by a running virtual machine. Log in to the VMware vSphere Management Assistant (v...

Investigating virtual machine file locks on ESXi

      Details Adding an existing virtual machine disk (VMDK) to a virtual machine that is already powered on fails.                 Failed to add disk scsi0:1. Failed to power on scsi0:1   Powering on the virtual machine results in the power on task remaining at 95% indefinitely. Cannot power on the virtual machine after deploying it from a template. Powering on a virtual machine fails with an error: Unable to open Swap File Unable to access a file since it is locked Unable to access a file <filename> since it is locked Unable to access Virtual machine configuration In the /var/log/vmkernel log file, you see entries similar to: WARNING: World: VM xxxx: xxx: Failed to open swap file <path>: Lock was not free WARNING: World: VM xxxx: xxx: Failed to initialize swap file <path>   When opening a console to the virtual machine, you may receive ...