[lkml]   [2006]   [May]   [24]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRe: [PATCH 3/4] myri10ge - Driver core


> We didn't get any ppc64 with PCI-E to run Linux so far. What performance
> drop should we expect with our current code ?

We have seen > 20% improvement on ppc64 running some networking
workloads when forcing 128 byte alignment (instead of 16 byte
alignment). DMA writes have to get cacheline aligned (in power of 2
steps) on some IO chips.

> I am not sure what you mean.
> The only ppc64 with PCI-E that we have seen so far (a G5) couldn't do
> write combining according to Apple.

Im thinking more generally, MTRRs are x86 specific and it would be good
to have a more generic way to enable write combining.

To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to
More majordomo info at
Please read the FAQ at

 \ /
  Last update: 2006-05-24 23:26    [W:0.060 / U:33.132 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site