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Data On Tap Queue Depth?

Hello all,

Just wondering what the Queue Depth settings are for data ontop 7.3.  I have read that NetApp uses Dynamic Queue Depths which lets the controllers / initators auto detect the queue length so its up to the OS to set the q depth so less resets are required at a host level, but is this available in Data Ontap 7.3? or all Data on tap?

If Data on tap does this is there any additional setup you need to do ?

Currnetly we are trying to setup some new AIX systems to are NetApp and was just wondering what the best Queue depth would be.

Thanks in advance,

Re: Data On Tap Queue Depth?

I always refer to the latest iSCSI and Fibre Channel Configuration guide at http://now.netapp.com/NOW/knowledge/docs/san/fcp_iscsi_config/config_guide/setting_up/concept/c_oc_set_config-limits-overview.html#c_oc_set_config-lim...

When you go through each configuration (single node or clustered) for each platform for the FC Queue Depth,  it is per port and is 1,720 per FCP Target port unless a FAS2020/2050 which is 737 per target port.

There are no settings to adjust this other than calculating the total host fan-in to each port.  If you see disk target queue depth settings, those are for vSeries from the NetApp controller fc initiator ports to back-end 3rd party disk but this does not apply to fc target ports to hosts.

Re: Data On Tap Queue Depth?

Scott, do you know if it's possible to increase the fc initiator queue depth on a V-series when connected to a 3rd party storage system? As you say, the iSCSI and Fibre Channel Configuration guide states that the maximum queue depth is 1,720, but I can't find a way to either determine the default initiator queue depth, or increase it.

Re: Data On Tap Queue Depth?

For v-series, check "options disk.target_port_cmd_queue_depth" to see the setting to the back-end array.  I think the max is 256.

Re: Data On Tap Queue Depth?

[ Edited ]

Sir,

 

Can we set queue depth per lun basis from netapp side

 

Regards

Murali