Re: big picture UDP/IP performance question re 2.6.18 -> 2.6.32

From: Eric Dumazet
Date: Wed Oct 05 2011 - 02:53:54 EST

Le lundi 03 octobre 2011 Ã 14:02 -0400, starlight@xxxxxxxxxxx a Ãcrit :
> At 06:16 PM 10/3/2011 +0200, Eric Dumazet wrote:
> >
> >It seems you use 4096 2MB hugepages, and your
> >machine has 1GB pages availabe, you could
> >try to use them.
> >
> >(boot cmd : hugepagesz=1GB hugepages=8 )
> Tried it and got errno 12 on the segment
> allocations. None were allocated, though
> the count is six and the largest is exactly
> 1GB. Don't have time to dig into it.

Thats pretty normal ;)

With 2MB pages, your segment size must be a 2MB multiple.

With 1GB pages, your segment size must be a .... 1GB multiple.

So only applicable is say you handle one big 8GB segment for example, or
2 4GB segments... Well you see the picture.

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