Esxi software iscsi queue depth

An hbas queue depth can be set when you configure it during system setup. On virtual machines running microsoft windows, increase the value of the scsi timeoutvalue parameter. Qlogic fc is the exception at 64, or software iscsi which is 128. Perfect, then lets have a look at io queues within esxi and how they. Also from the vdbench printout, the active queue depth in the vm for that. Sw iscsi queue depth description this option is also known as disk queue length dqlen. Schednumreqoutstanding which is a perdevice setting, which. If there is more than one vm on the datastore then this value is the minimum of the hba device queue depth or the disk. For information on changing queue depth for iscsi adapters and virtual machines, see vsphere troubleshooting. Maximum software iscsi io size in kb requires reboot. Lun and hba queue depth on esx i hosts i previously posed a few questions about the behavior of vsphere s sioc and lun adaptive queue depth algorithm and have a few observations to report. For troubleshooting, you can run esxcli commands in the esxi shell.

While adjusting queue depth on a hardware hba fcp or iscsi is a common performance tweak assuming you have discussed the change with your storage vendor first tweaking the same setting for the iscsi software initiator doesnt have as much of an effect. On the other hand, the paravirtual adapter has a default queue depth of 256 per. Adjust maximum queue depth for software iscsi vmware docs. See getting started with vsphere commandline interfaces. I used iscsi for testing where the cli command looks like the following. Understanding vmware esxi queuing and the flasharray. The default is 32, and the valid range is 1 to 255.

This article is in response to the post more questions about queues. Transmitting data over unsecured channel is not recommended. I had a question asked the other day about iscsi software initiator queue depth. Again, we need to verify that the disk queue depth is 192 by running esxtop with the u. By default esxi restricts iscsi io to a maximum of 128k, this should be. If you notice unsatisfactory performance for your software iscsi luns, change their maximum queue depth by running the esxcli commands. Understanding vmware esxi queuing and the flasharray cody. For the software iscsi initiator, set the queue depth. While adjusting queue depth on a hardware hba fcp or iscsi is a common performance. Configuring vmware vsphere 6 with oracle flash storage systems. This value is identified by looking at the configured hba queue depth limit, which is generally 32 qlogic fc is the exception at 64, or software iscsi which is 128. This is due to the use of host multipathing, where there are multiple paths to each physical lun. Again, we need to verify that the disk queue depth is 192 by running esxtop with the u command. Howto check queue depth of storage adapter or storage device.