TonyJK
Enthusiast
Enthusiast

Only 1 ESXi Host gets SSD

Hi,

We are running a cluster of 3 ESXi 5.1 Hosts.  2 of them are Xeon E7440 @ 2.4GHz and 1 of them is Xeon X5460 @ 3.16GHz.

We are going to replace the Xeon X5460 Server with a new physical server.

We understand that SSD does improve the performance of ESXi BUT if there is only one of them gets SSD while the other two don't, is there any improvement OR tweaking that can be done ?

Moreover, we are only running Enterprise License.

Thanks

Tags (1)
Reply
0 Kudos
CoolRam
Expert
Expert

You can configure the Host cache in SSD Drive . so the transaction from the cache will improve.

If you find any answer useful. please mark the answer as correct or helpful.
Alistar
Expert
Expert

Hello,

if your servers are using local storage and only one of them will have an SSD, the first thing I'd recommend is getting two SSDs and putting them to RAID1 if you plan to use them on IO intensive VMs (databases) - you'll see a stellar performance from these servers once you migrate them there.

If you have one and only one, you can also use it as a vSphere Flash Read Cache vFRC | VMware vSphere Blog - VMware Blogs, which will boost your read performance for the VMs you choose.

Stop by my blog if you'd like :slightly_smiling_face: I dabble in vSphere troubleshooting, PowerCLI scripting and NetApp storage - and I share my journeys at http://vmxp.wordpress.com/
TonyJK
Enthusiast
Enthusiast

Hi,

Many thanks for your advice.

May I ask a silly question -

Does vSphere Flash Read Cache = Host Cache ?

Thanks

Reply
0 Kudos
TonyJK
Enthusiast
Enthusiast

Dear Alistar,

Many thanks for your advice.

The current practice, we don't use local storage for VM.

I have a quick look of setting vSphere Flash Read Cache for VM.  Just would like to know if that VM is migrated to the other 2 servers without SSD, will the cache setup will not function automatically ?

Thanks again

Reply
0 Kudos
CoolRam
Expert
Expert

It Will work just you need to ensure the  caching you are not migrating with VM. it should remain with the datastore when it will ask for swap migration.

If you find any answer useful. please mark the answer as correct or helpful.
Reply
0 Kudos
TonyJK
Enthusiast
Enthusiast

Dear CoolRAM,

Is it the option that listed in VMWare KB - Choose "Do not migrate the cache contents" ?

If yes, just wonder whether this feature also available for ESXi 5.1 ?

From VMWare KB 2051645

To migrate a virtual machine that is configured with a vSphere Flash Read Cache resource:

  1. In the vSphere Web Client, right-click the virtual machine and click Migrate.
  2. Click Change Host.
  3. Select the destination host.
  4. Under Select Flash Read Cache Migration Settings, choose what you want to do with the existing virtual machine flash cache:
    • To keep the current cache select Always migrate the cache contents
    • To discard and rebuild the cache on the new host select Do not migrate the cache contents.
Reply
0 Kudos