Re: Very slow writes with mptsas

[bloch@verdurin.com]

On Wed, 06 Jun 2007, Douglas Gilbert wrote:

> Matthew Jacob wrote:
> > The FreeBSD problem was fixed by Scott Long a couple of days ago by
> > doing some cut through SAS stuff that enabled Write Cache for SATA
> > drives. Why LSI-Logic couldn't just blitheringly synthesize mode page
> > 8 is beyond me, but okay.
> > 
> > I dunno whether the issue here is the same one Scott tackled- probably
> > given the messages. Eric- you listening in on this?
> 
> Matt,
> Just in case Eric doesn't answer, I suspect if the
> HBA firmware can be upgraded (from Dell or LSI?) then
> WCE (write cache enable) in the caching mode page
> will be supported. It is one of the few mode page
> settings that is required to be implemented in SAT.
> 
> The other field that should be changeable is DRA
> (disable read ahead). Both work on my LSI SAS HBA.
> 
> Doug Gilbert
> 

I upgraded to the latest Dell firmware, but the kernel message is the
same - write cache disabled, and the write speed is still very bad.  No
sign of new changeable options.

Can't actually see any firmware on the LSI site.

Adam