Will my server be bottlenecked?

[PJ3]

Hi Guys,

I have been obsessing over this configuration of a server and would appreciate some input as I am afraid of forging ahead and implementing a crippled system.

We have a DL385 G7 with an onboard P420i + BBWC + SAS Expander card and 11 x 146GB 15K SAS drives. This server is going to be rebuilt as an ESXi server hosting 7 VM's with a wide range of uses. I am confident of having enough CPU and RAM but am worried about disk throughput. Sadly, I cannot provide any I/O requirements for the eventual VMs as they will be fresh built. .

I was planning to split off two or three of the high disk load servers (2 x Terminal Servers and 1 File Server also hosting a mail server) onto a RAID 10 and having a second RAID 5 for all other servers.

My question was whether what I propose above is a good idea but also whether it is wise to have a single controller managing both drive cages and two RAID arrays? Will I create a bottleneck?

Any help would be well received :) Thanks

[waaronb]

I don't know for sure, but I see one problem is that you plan to put all of your heavy I/O systems onto one array. It might work better if you split the heavy loads among different arrays, otherwise you might see a big performance problem on the heavily loaded array and the other one is doing just fine.

You could try filling all of the drive bays and create more than just 2 arrays. Depending on the space needed for each system just give each heavy I/O virtual system it's own set of drives. I don't know if the email server you mentioned is Exchange... if so, it is really hard on the drive subsystem so it needs as many drives as you can give it.

The controller itself can probably do okay... the shared write-cache could be a drawback, but it all comes down to just how heavily loaded it ends up being. Without any real numbers to work from it's hard to predict.

Like I said though, you can add more disks, you could upgrade the array cache to 2GB instead of 1GB or whatever it has right now, and just be prepared to make some changes if you see problems after it's all been implemented.

[Sbrown]

I'd avoid RAID-5 with virtualization - specifically ESXi 5.x it will throw too many errors for latency!

You have a P420 in that server? You should make use of hp smartcache to offload read-caching to SSD!

You will find best performance with multiple lun's with esxi!