Bug 12157

Summary:	Avoid rebuilds when recipe specific sysroot has not changed
Product:	[Build System, Metadata & Runtime] BitBake	Reporter:	Ola Nilsson <ola.x.nilsson>
Component:	bitbake	Assignee:	Richard Purdie <richard.purdie>
Status:	RESOLVED FIXED	QA Contact:
Severity:	enhancement
Priority:	Medium	CC:	poky.bs.watcher, poky.watcher, randy.macleod
Version:	unspecified
Target Milestone:	Future
Hardware:	x86
OS:	Multiple
Whiteboard:
OS type for building Yocto:	---	Type of Regression:	---
Verified:		Documentation change:	Yes (doc changes required)

Description Ola Nilsson 2017-10-03 08:19:02 UTC

Many packages such as libraries, kernel modules, and the kernel itself can trigger many rebuilds of other packages even when they are not needed.  

A shared library that is rebuilt but has no interface changes will trigger rebuilds on all recipes that DEPENDS on it, even if it is not really needed.  

Could the populate_sysroot task somehow check a hash of the exported files to see whether dependent packages really need to rebuild?

Comment 1 Richard Purdie 2019-10-03 15:33:01 UTC

We now have the hash equivalency server which addresses this problem.