id	summary	reporter	owner	description	type	status	component	version	severity	resolution	keywords	cc	stage	has_patch	needs_docs	needs_tests	needs_better_patch	easy	ui_ux
24720	using middleware.common to append slashes causes extra overhead to all requests that do not end in a slash	Jay Cox	nobody	"Checking if a url is valid is just as costly as fully resolving the url, so when the common middleware checks if it should append a slash it is fully doubling the url resolution overhead (which is about 5%) (this overhead only applies to urls that do not already end in a slash)

By deferring the checks until the ''process_response'' phase we can make sure that we only pay the price for urls that actually need a slash appended (that is to say would actually return a 404).

Pull request:
https://github.com/django/django/pull/4574"	Cleanup/optimization	closed	Core (Other)	dev	Normal	fixed	optimization middleware common		Accepted	1	1	0	0	0	0