Re: SATA RAID5 speed drop of 100 MB/s

[Tejun Heo <htejun@gmail.com>]

Carlo Wood wrote:
> For what it's worth... I tried applying
> 
> --- a/drivers/ata/ahci.c
> +++ b/drivers/ata/ahci.c
> @@ -516,6 +516,8 @@ static void ahci_save_initial_config(struct pci_dev *pdev,
>          * reset.  Values without are used for driver operation.
>          */
>         hpriv->saved_cap = cap = readl(mmio + HOST_CAP);
> +       hpriv->saved_cap &= ( (1<<28) | (1<<17) );
> +       hpriv->saved_cap |= (1 << 27);
>         hpriv->saved_port_map = port_map = readl(mmio + HOST_PORTS_IMPL);

Hmmm... That's super-odd.  You win my oddest-of-the-month award.  :-)

I'll think about it a bit.  Please stand by.

-- 
tejun