Solved

Where should I use my faster disk array in a Virtual Machine?  System or Data?

Posted on 2011-09-05
2
251 Views
Last Modified: 2012-05-12
The current ESXi server I am building has access to 2 local data strores.  both consist of 2 drives mirrored.  The first pair of drives are 10k SAS (300Gb) .  The second pair of drives are 7k SAS (500Gb).

For my Windows SQL server I'd planned to put the system vmdk file on the 10k datastore (where my c:\windows would reside).  Then use a thin porivisioned vmdk on the 7k datastore for the D: drive and the SQL databases.
The same would apply for my IIS server - using the D:drive for the inetpub dir.

Would I be better doing this the other way round ?  So that I was using the faster datastore for the D: drives - the SQL and inetpub data respectively?
0
Comment
Question by:touch-base
2 Comments
 
LVL 118

Accepted Solution

by:
Andrew Hancock (VMware vExpert / EE MVE) earned 500 total points
ID: 36485648
The 10k disks are double the IOPS that the 7k disks have.

I would install the OS on the 7k (it's only boot-up).

if you want performance, I would install SQL Database and Logs on the 10k.

But checkout the performance for yourself using the following:-

1. Disktt
http://www.snapfiles.com/get/disktt.html

2. HDTach
http://www.simplisoftware.com/Public/index.php?request=HdTach

3. CrystalDiskMark
http://crystalmark.info/software/CrystalDiskMark/index-e.html

4.IOMeter
http://www.iometer.org/

 Characterize storage performance and correct: Storage Performance Analysis and Monitoring
0
 
LVL 47

Expert Comment

by:dlethe
ID: 36485780
You need to realize that no matter what you do, vmware will only make I/O go slower as it adds a level of encapsulation.  Can you go direct I/O, i.e, let the ESXi server itself directly control disk I/O by talking to a dedicated controller?

The most efficient thing would be to set up a NTFS file system with 64KB I/O for D:\, where the SQL is, and go with a smaller C:\ drive with default NTFS for the O/S & swap.  

If you must use vmware, then you should just make a single logical drive as vmware will do I/O in chunks based on the size of the pool anyway, so better to have one large pool so it can cache more I/O.   Remember, every I/O on C or D affects both disks, and you technically can do fewer I/Os on a combined C:\ drive due to the fixed block size that vmware will do

Summary: If using VMWARE,  just partition a single logical disk if it must be under control of vmware.  If you can dedicate the controller to the VM, then split the volume into 2 partitions, and you will be much better off.
0

Featured Post

How your wiki can always stay up-to-date

Quip doubles as a “living” wiki and a project management tool that evolves with your organization. As you finish projects in Quip, the work remains, easily accessible to all team members, new and old.
- Increase transparency
- Onboard new hires faster
- Access from mobile/offline

Join & Write a Comment

HOW TO: Upload an ISO image to a VMware datastore for use with VMware vSphere Hypervisor 6.5 (ESXi 6.5) using the vSphere Host Client, and checking its MD5 checksum signature is correct.  It's a good idea to compare checksums, because many installat…
In this article, I will show you HOW TO: Create your first Windows Virtual Machine on a VMware vSphere Hypervisor 6.5 (ESXi 6.5) Host Server, the Windows OS we will install is Windows Server 2016.
Advanced tutorial on how to run the esxtop command to capture a batch file in csv format in order to export the file and use it for performance analysis. He demonstrates how to download the file using a vSphere web client (or vSphere client) and exp…
This tutorial will walk an individual through the steps necessary to enable the VMware\Hyper-V licensed feature of Backup Exec 2012. In addition, how to add a VMware server and configure a backup job. The first step is to acquire the necessary licen…

747 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question

Need Help in Real-Time?

Connect with top rated Experts

11 Experts available now in Live!

Get 1:1 Help Now