Re: Resets on sil3124 & sil3726 PMP

[Tejun Heo <htejun@gmail.com>]

Hello,

Petr Vandrovec wrote:
> I have recompiled kernel with all debugging disabled, and it brought me
> 1.5MBps, so it is still consistently 1MBps slower than on sil. Disabling
> NCQ seems to improve concurrent access a bit (for which I have no
> explanation), while slows down single drive scenario:
> 
> With NCQ:
> 
> 1TB alone: 81.22, 79.86
> 1TB+1TB:   56.28+56.70, 53.51+56.11
> 
> Without NCQ:
> 
> 1TB alone: 79.78, 80.82
> 1TB+1TB:   57.99+58.12, 56.50+56.46
> 
> 3512 sil, no NCQ:
> 
> 1TB alone: 82.28, 82.18
> 1TB+1TB:   47.20+47.54    # Here apparently command based switching or
> 1.5Gbps link between device and PMP becomes bottleneck

Hmmmm.... Weird.  Is the different still there if you take PMP out of
the picture?

> And it seems that I observe what other poster pointed out - that
> apparently all SiI chips are limited somewhere around 120-130MBps, and
> cannot do more even if you pretty ask...

Yeah, that seems to be the hardware limit and is consistent with what I
hear from non-linux people too.

-- 
tejun