id	summary	reporter	owner	description	type	status	priority	milestone	component	version	resolution	keywords	cc	os	architecture	failure	difficulty	testcase	blockedby	blocking	related
5113	Huge performance regression of 7.0.2, 7.0.3 and HEAD over 7.0.1 and 6.12 (MonoLocalBinds)	daniel.is.fischer		"Exploring ways to make show for `Double` and `Float` faster, I encountered a terrible performance regression. Time increased about 20-fold, allocation about 75-fold.

With 6.12.3 and 7.0.1, the new code is nearly twice as fast as the old and allocates less than a third. With 7.0.2, 7.0.3 and the HEAD (7.1.20110329), the new code is over ten times slower than the old and allocates more than twenty times as much.

In 7.0.3's core at least some local bindings appear as polymorphic functions which are inlined by 7.0.1. And indeed, compiling with -XMonoLocalBinds rectifies matters. Nevertheless, that shouldn't happen."	bug	closed	normal		Compiler	7.0.3	fixed	performance, MonoLocalBinds		Linux	x86	Runtime performance bug	Unknown	perf/should_run/T5113