DL380 G5 and P400 Controller performance issue with VM

[Richard Casellas]

I have a VMWare server running on a DL380 G5 with a P400 controller. The controller is set to 100% Read /0% Write. This seems to be the default when then contoller does not have a backup battery. The performance on the box is horrible with just one vm server running. Previously this was a live box but had to be taken offline because of this problem. Does anyone know or have experience a simular issue with VMWare ESX on this type of server.

[Matti_Kurkela]

Yes, the absence of a backup battery often has a significant performance impact.

The exact effect depends on the read/write patterns of the application workload: I think there was a recent thread where the speed of some database operations was improved by about 4x with the addition of the battery.

MK

[Richard Casellas]

So basically, by adding a battery and changing the read/write to lets same as an example 50% Read / 50% write, the performance should improve significantly, correct.

[Graeme Bray]

We have had several ML350's and other machines running without the Battery Backup Write Cache that were having I/O issues. We added the battery and the performance issues pretty much disappeared.