Displaying bug patch badges in listing is inefficient, causes many timeouts

[Eleanor Berger]

The way we query for patches to display as badges on bug listings is very inefficient (one query per bug) and causes many timeouts.

[Eleanor Berger (intellectronica)]

See OOPS-1486ED402 for example.

[Eleanor Berger (intellectronica)]

~jml, who also gets to say "i told you so", having spotted the problem in review, tells me that may be a good example of how this can be optimized is found in lib/lp/code/browser/branchlisting.py

[Björn Tillenius (bjornt)]

On Mon, Jan 25, 2010 at 10:15:25AM -0000, Tom Berger wrote:
> ~jml, who also gets to say "i told you so", having spotted the problem
> in review, tells me that may be a good example of how this can be
> optimized is found in lib/lp/code/browser/branchlisting.py

I would suggest looking in lib/lp/bugs/browser/bugtask.py insted, to see
how it's done for the rest of the badges in the bug listings. Search for
BugListingBatchNavigator. It should be easy to extend it to handle
patches as well.

[Eleanor Berger (intellectronica)]

Tested the fix on staging and it works well.