Re: Very slow HP 8 Internal Port SAS HBA with RAID 0, 1 on Hot Plug SAS/SATA Models (LSI SAS1068 - mpt)

Stefan Lambrev wrote:
> Richard Tector wrote:
>> Stefan Lambrev wrote:
>>> Hi list,
>>>
>>> I'm having problems with the raid controller of HP ProLiant DL140 G3 
>>> Server and RELENG_7
>>>
>>> I have 2x 500GB SATA HDDs configured as mirror, but the write speed 
>>> is very slow ~7MB/s.
>>>
>>> I guess that there is no battery for the raid controller and the 
>>> write cache is off, but 7MB/s ..
>>> Also there is no way to see the status of the raid from FreeBSD ?
>>>
>>> Any ideas how to improve this?
>>
>> Write cache is the most probable cause.
>> You can force it on with:
>> hw.mpt.enable_sata_wc=1

> This have to be put in /boot/loader.conf as I do not see such sysctl?
> Anyway I'll force the write cache to be always on from the raid 
> configuration if this does not work.

If you have the option in the RAID bios. Try that first.
Failing that, yes, pop that in /boot/loader.conf, and it should do the 
trick.

Regards,

Richard