Storage I/O control benefit with one host only?

[yannara]

I noticed that vCenter offers I/O control option to every datastore available, by default it is not turned on. I started to reading about this, and everywhere is said that this is benefit in clustered enviroments or/and with shared storage. But how about local storage? Do I get any benefit in this kind of lab enviroment?

1x ESXi 5.1
1x vCenter (VM located at the same host)

4x SATA 1, SATA 2 and SATA 3 disks.

Thanks!

[JCMorrissey]

Hi Yannara,

Think you posted something similar just there

Just seen this one - notice you are using DAS storage - in my instance we have fibre in our branch offices which is supported - unfortunately DAS isn't

See:

http://pubs.vmware.com/vsphere-51/index.jsp?topic=%2Fcom.vmware.vsphere.storage.doc%2FGUID-8AE88758-...

"

Storage I/O Control Requirements

Storage I/O Control has several requirements and limitations.

■	Datastores that are Storage I/O Control-enabled must be managed by a single vCenter Server system.
■	Storage I/O Control is supported on Fibre Channel-connected, iSCSI-connected, and NFS-connected storage. Raw Device Mapping (RDM) is not supported.
■	Storage I/O Control does not support datastores with multiple extents.
■	Before using Storage I/O Control on datastores that are backed by arrays with automated storage tiering capabilities, check the VMware Storage/SAN Compatibility Guide to verify whether your automated tiered storage array has been certified to be compatible with Storage I/O Control. Automated storage tiering is the ability of an array (or group of arrays) to migrate LUNs/volumes or parts of LUNs/volumes to different types of storage media (SSD, FC, SAS, SATA) based on user-set policies and current I/O patterns. No special certification is required for arrays that do not have these automatic migration/tiering features, including those that provide the ability to manually migrate data between different types of storage media.

Hope this helps!

[chriswahl]

To answer the great question, yes. SIOC is a datastore technology and works regardless of the number of hosts or clusters in the vSphere data center. If for some reason you had a noisy VM, SIOC would throttle the queue. You can test it out in the lab assuming you have a supported storage protocol.

[depping]

Chris Wahl wrote:

To answer the great question, yes. SIOC is a datastore technology and works regardless of the number of hosts or clusters in the vSphere data center. If for some reason you had a noisy VM, SIOC would throttle the queue. You can test it out in the lab assuming you have a supported storage protocol.

Please note that SIOC is a datastore wide scheduler for multiple hosts. If a single host accesses a datastore then the local scheduler (SFQ) handles the scheduling per VM based on the assigned  shares.

So if you have a lab with a single host and a couple of VMs then there is no real point in enable SIOC on that datastore.

[yannara]

And what about sata interface? Somewhere is written only about iscsi.

[Gkeerthy]

The SIOC only looks the Datastore, which in turn made up of FC LUN or ISCSI LUN or NFS, and these are again made up of SSD or SAS or SATA HDD, So based on the type of HDD used to make a LUN defines the SIOC threshold, and as mentioned by Duncan - There is no point of enabling for one host, you can see more results and how it works in real time in my blog

http://pibytes.wordpress.com/2013/01/19/magic-effect-of-sioc-vmware-storage-input-output-control-in-...

Of course you will get the similar functionality with one host, Simply just use and set shares for the VMDK and the ESXi host use Host-Level Disk Scheduler, and you will get he results.