Intel SRCS16 on ESX4 - Poor write performance

[mtaller]

Hi everyone !

I need to change HD on one of my ESX hosts that only have 250Gb of total space, so we buy 5 HD of 1Tb.

This week-ends, I put another Raid controler (Intel SRCS16) and connect one 1Tb just to copy VM from old HD to the new.

Creating Raid array have taken less than 1min.

Creating partition on the raid drive have taken less than 1min. (with fdisk)

Formating partition have taken more than 3 hours (with mkfs.ext3)

Tested write performance with : time dd if=/dev/zero of=/mnt/share/test.test bs=1M count=1024

And have taken around 18min. (1Mb/s)

Some research on google I did'nt find some usefull links.

On Vmware Communities, I found this : http://communities.vmware.com/thread/105552?start=0&tstart=0

But it doesn't work.

Someone have any idea ?

Thanks for your help

[rogard]

Is the backup battery attached/charged?

[mtaller]

Don't know. I currently unable to access server.

But if I remember well, there are no battery backup on the controller.

[zerda · Accepted solution]

Intel SRCS16 has extremely poor write performance without write cache enabled. For normal operations with write cache you should have BBWC (battery backup). Enabling write cache without BBWC can lead to loss of data in case of power failure.

UPD. See .

[mp04279]

Although 32 physical drives are allowed per logical array, no more than 2TBytes are allowed per logical drive. This info comes straight out of their manual. Hope this helps.

[mtaller]

It seem that the SRCS16 need the battery to get best write performance.