Re: [libvirt] [PATCH 4/5] qemu: Build command line for NUMA tuning

["Daniel P. Berrange" <berrange redhat com>]

On Thu, May 05, 2011 at 05:38:29PM +0800, Osier Yang wrote:
> Just prepend numactl command line to qemu command line.
> ---
>  src/qemu/qemu_command.c |   16 ++++++++++++++++
>  1 files changed, 16 insertions(+), 0 deletions(-)
> 
> diff --git a/src/qemu/qemu_command.c b/src/qemu/qemu_command.c
> index 2205ed1..156fdfb 100644
> --- a/src/qemu/qemu_command.c
> +++ b/src/qemu/qemu_command.c
> @@ -2762,7 +2762,23 @@ qemuBuildCommandLine(virConnectPtr conn,
>          break;
>      }
>  
> +#ifdef HAVE_NUMACTL
> +    /* XXX: Logic here to build numactl commmand line need to be changed if
> +     * more NUMA tuning related stuffs in future.
> +     */
> +    if (def->numatune.membind.nodeset) {
> +        cmd = virCommandNewArgList(NUMACTL,
> +                                   "-m",
> +                                   def->numatune.membind.nodeset,
> +                                   NULL);
> +
> +        virCommandAddArgList(cmd, emulator, "-S", NULL);
> +    } else {
> +        cmd = virCommandNewArgList(emulator, "-S", NULL);
> +    }
> +#else
>      cmd = virCommandNewArgList(emulator, "-S", NULL);
> +#endif

NACK to this approach. We should be using the libnuma APIs to set the
memory binding for the process directly, and not running the numactl
command.

Regards,
Daniel
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