Dell RD1000 internal SATA removable disk performance

[snorris]

Unlike most of the older posts concerning the Dell RD1000 and how to utilize the drive in a guest VM, I want to use the drive for performing backups on the ESX(i) (free version) host. I have no problems adding the drive as a datastore using the vSphere client and ghettoVCB actually works, however throughput (write speed) is awful (~2MB/s). It took ghettoVCB approx. 2 hours and 35 minutes to backup a 16GB VM, which is totally unacceptable. I don't have the option of using network based resources for backups, which is why this server was purchased with the RD1000.

Has anyone had any success using the RD1000 at the host level? VMware ESXi is treating/mapping this SATA device as a block SCSI device. Is there any tweaks to be made at the kernel level that would affect performance?

[DSTAVERT]

Disk writes are usually poor when there is no disk write caching. You will probably need a hardware RAID controller with some form of protected write caching (battery or flash) enabled.

[markpiontek]

Snorris,

I have had a hard time finding info on the RD1000 and ESXi 4.  Can you tell me if it can be made available to a guest operating system?  Not looking to backup the VM itself, but data within the VM.

Thanks.

[snorris]

I'm not able to say for certain since that's not what I was trying to do, but I do recall seeing various posts where people were successful in exposing the RD1000 to the guest vm. You'll just have to do a google search for something like: vmware guest access RD1000. Pay particular attention to mention of RDM (Raw Disk Mapping).

[markpiontek]

Thanks for the reply.  I have been doing some searching already, which is how I landed on this thread.  Think I'm going to go with a different method.

Thanks.