vSphere and HP EVA 4400 storage performance

[knodlerc]

Hi all

Maybe someone can help me.

Today I have a virtual infrastructure composed by two blade servers (2 cpus each) and a EVA 4400 storage with one full enclosure (12x400GB - 10krpm). The servers and the storage are connected by fiber channel (4GB connection).

I was oriented by the company who setup the first architecture to store each VM in a single LUN at the EVA. This means that my Active Directory VM with 30GB of vdisk is stored in a 40GB LUN. They told me that this was better for the VM performance, since it will be "alone" at the LUN. This is correct? Should I continue to do that or it's better to store as much VM as I can on a vdisk with max 256GB (smallest block)?

I'm asking this because I'm planning and upgrade at the infrastructure: add another blade server, upgrade the memory to 64GB on each host and add another enclouser at the EVA storage (+12x400GB - 10krprm).

Today I have a considerable I/O usage because I run 5 noon productive SAP environments with Oracle database, one Oracle 11g database and several applications and infrastructure servers. With the upgrade I will add to the storage the following VM: Exchange (~600 mailboxes), SQL server, IIS, 2x Oracle 11g, Print server, Nagios, ...

Please let me know your thoughts about the LUN size for the VMs and the impacts on the performance.

Best regards,

Christian

[AntonVZhbankov · Accepted solution]

>I was oriented by the company who setup the first architecture to store each VM in a single LUN at the EVA. This means that my Active Directory VM with 30GB of vdisk is stored in a 40GB LUN. They told me that this was better for the VM performance, since it will be "alone" at the LUN.

Hmmm... Another "all knowing" consultants without actual knowledge.

If your multiple LUNs share the very same physical disks - it absolutely doesn't matter in terms of performance if you VMs are placed on dedicated LUNs or shared. But you lose flexibility with dedicated LUNs.

This is correct? Should I continue to do that or it's better to store as much VM as I can on a vdisk with max 256GB (smallest block)?

Shared LUN and multiple VMs on it will run absolutely fine and you will be able to manage space much easily, especially with thin disks.

>Today I have a considerable I/O usage because I run 5 noon productive SAP environments with Oracle database, one Oracle 11g database and several applications and infrastructure servers. With the upgrade I will add to the storage the following VM: Exchange (~600 mailboxes), SQL server, IIS, 2x Oracle 11g, Print server, Nagios, ...

In this case think about separating VMs with high I/O load and low load, and place them on separate disk groups, so they won't affect each others performance for sure.

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