Re: A scrub daemon (prezeroing)

[Ralf Baechle]

On Thu, Jan 27, 2005 at 07:12:29AM -0600, Robin Holt wrote:

> > Some architectures tend to have spare DMA engines lying around. There's
> > no need to use the CPU for zeroing pages. How feasible would it be for
> > scrubd to use these?
> 
> An earlier proposal that Christoph pushed would have used the BTE on
> sn2 for this.  Are you thinking of using the BTE on sn0/sn1 mips?

On BCM1250 SOCs we've gone a step beyond that and use the Data Mover to
clear_page(), see arch/mips/mm/pg-sb1.c.  It's roughly comparable to the
SN0 BTE.  Broadcom has meassured a quite large performance win for such
a small code change.

  Ralf
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/