Hello Stefan,
check if the battery on RAID in ok!, I have exactly the  situation, and
found
that there is no RAID battery on the controller. If there is no battery,
the write cache is disabled

Chavdar

On Fri, Nov 13, 2015 at 12:26 PM, Stefan Folkerts <stefan.folkerts AT gmail DOT 
com
> wrote:

> Hello all,
>
> We have a situation where one of our customers is showing very slow
> performance on writing to a disk or file type storage pool on disk.
>
> Writing to tape with TSM is fast.
> Writing a database backup to disk is fast (this writes to the same drives
> but it writes to the devclass definition and not the storagepool definition
> of course)
> Writing to a disk or file type storagepool is very slow (10-15MB/s)
> Writing to the same disk in Linux is fast (200+ MB/s)
>
> I found and read this article:
> http://www-01.ibm.com/support/docview.wss?uid=swg21137676
>
> But before I make a call with IBM I was hoping some of you might know the
> correct settings for disk/file type storagepools on this type of local
> storage.
>
> Regards,
>     Stefan
>