[PATCH 07/11] Be particular over check_set and series prefetch for /list/

[Stephen Finucane]

On Fri, 2018-08-10 at 18:01 +1000, Stewart Smith wrote:
> At this point it shaves at most 1-2ms off the query time for
> /linuxppc-dev/list/
> 
> Signed-off-by: Stewart Smith <stewart at linux.ibm.com>

I wasn't able to see anything notable in this locally but it also
didn't harm performance so

Reviewed-by: Stephen Finucane <stephen at that.guru>

Stephen

> ---
>  patchwork/views/__init__.py | 6 +++++-
>  1 file changed, 5 insertions(+), 1 deletion(-)
> 
> diff --git a/patchwork/views/__init__.py b/patchwork/views/__init__.py
> index 96fd0798af5a..64d3d5f9f22d 100644
> --- a/patchwork/views/__init__.py
> +++ b/patchwork/views/__init__.py
> @@ -19,6 +19,7 @@
>  
>  from django.contrib import messages
>  from django.shortcuts import get_object_or_404
> +from django.db.models import Prefetch
>  
>  from patchwork.compat import is_authenticated
>  from patchwork.filters import Filters
> @@ -27,6 +28,8 @@ from patchwork.models import Bundle
>  from patchwork.models import BundlePatch
>  from patchwork.models import Patch
>  from patchwork.models import Project
> +from patchwork.models import Check
> +from patchwork.models import Series
>  from patchwork.paginator import Paginator
>  
>  
> @@ -290,7 +293,8 @@ def generic_list(request, project, view, view_args=None, filter_settings=None,
>      patches = patches.only('state','submitter','delegate','project','name','date')
>  
>      # we also need checks and series
> -    patches = patches.prefetch_related('check_set', 'series')
> +    patches = patches.prefetch_related(Prefetch('check_set', queryset=Check.objects.only('context','user_id','patch_id','state','date')))
> +    patches = patches.prefetch_related(Prefetch('series', queryset=Series.objects.only('name')))
>  
>      paginator = Paginator(request, patches)
>