Re: [PATCH 00 of 10 v3] Automatic NUMA placement for xl

[Ian Campbell <ian.campbell@citrix.com>]

(resend as I don't think I had SMTP setup properly on my laptop, sorry if you get this twice!)

On Wed, 2012-07-04 at 12:17 -0400, Dario Faggioli wrote:
> Hello,
> 
> Third version of the NUMA placement series Xen 4.2.

Starting an HVM guest (although I don't suppose it is HVM specific) on a
none NUMA system I get this:

        libxl: debug: libxl_numa.c:270:libxl__get_numa_candidates: only 1 node. no placement required
        libxl: detail: libxl_dom.c:175:numa_place_domain: 0 NUMA placement candidates found
        libxl: notice: libxl_dom.c:180:numa_place_domain: NUMA placement failed, performance might be affected
        
this being a non-NUMA system I suppose it is not the end of the world.
It'd be nice to avoid the warning though -- perhaps
libxl__get_numa_candidates should either not special case single node
systems or it should manually return the trivial candidate set?

> All the comments received during v2's review have been addressed (more details
> in single changelogs).
> 
> The most notable changes are the following:
>  - the libxl_cpumap --> libxl_bitmap renaming has been rebased on top of the
>    recent patches that allows us to allocate bitmaps of different sizes;
>  - the heuristics for deciding which NUMA placement is the best one has been
>    redesigned, so that it now provides total ordering.
> 
> Here it is what this posting contains (* = acked during previous round):
> 
>  * [PATCH 01 of 10 v3] libxl: add a new Array type to the IDL
>    [PATCH 02 of 10 v3] libxl,libxc: introduce libxl_get_numainfo()
>  * [PATCH 03 of 10 v3] xl: add more NUMA information to `xl info -n'
>    [PATCH 04 of 10 v3] libxl: rename libxl_cpumap to libxl_bitmap
>    [PATCH 05 of 10 v3] libxl: expand the libxl_bitmap API a bit
>  * [PATCH 06 of 10 v3] libxl: introduce some node map helpers
>    [PATCH 07 of 10 v3] libxl: explicitly check for libmath in autoconf
>  
> Is where data structures, utility functions and infrastructure are introduced.
> 
>  * [PATCH 08 of 10 v3] libxl: enable automatic placement of guests on NUMA nodes
>  * [PATCH 09 of 10 v3] libxl: have NUMA placement deal with cpupools
> 
> Host the core of the mechanism.
> 
>  * [PATCH 10 of 10 v3] Some automatic NUMA placement documentation
> 
> For some more documentation.
> 
> Thanks a lot and Regards,
> Dario
>