From: Linus Torvalds Date: Fri, 14 Dec 2012 15:20:43 +0000 (-0800) Subject: Revert "sched: Update_cfs_shares at period edge" X-Git-Tag: omap-for-v3.8/fixes-for-merge-window-v4-signed~19 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=17bc14b767cf0692420c43dbe5310ae98a5a7836;p=pandora-kernel.git Revert "sched: Update_cfs_shares at period edge" This reverts commit f269ae0469fc882332bdfb5db15d3c1315fe2a10. It turns out it causes a very noticeable interactivity regression with CONFIG_SCHED_AUTOGROUP (test-case: "make -j32" of the kernel in a terminal window, while scrolling in a browser - the autogrouping means that the two end up in separate cgroups, and the browser should be smooth as silk despite the high load). Says Paul Turner: "It seems that the update-throttling on the wake-side is reducing the interactive tasks' ability to preempt. While I suspect the right longer term answer here is force these updates only in the cross-cgroup case; this is less trivial. For this release I believe the right answer is either going to be a revert or restore the updates on the enqueue-side." Reported-by: Linus Torvalds Bisected-by: Mike Galbraith Acked-by: Paul Turner Acked-by: Ingo Molnar Signed-off-by: Linus Torvalds --- Reading git-diff-tree failed