From: Ingo Molnar <mingo@elte.hu>
To: Peter Zijlstra <peter@programming.kicks-ass.net>,
Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com>,
Dhaval Giani <dhaval@linux.vnet.ibm.com>,
linux-kernel@vger.kernel.org
Subject: Re: Make yield_task_fair more efficient
Date: Thu, 21 Feb 2008 07:04:27 +0100 [thread overview]
Message-ID: <20080221060427.GA9159@elte.hu> (raw)
In-Reply-To: <20080221053321.GA26918@balbir.in.ibm.com>
* Balbir Singh <balbir@linux.vnet.ibm.com> wrote:
> __pick_last_entity() walks the entire tree on O(lgn) time to find the
> rightmost entry. This patch makes the routine more efficient by
> reducing the cost of the lookup
hm, i'm not sure we want to do this: we'd be slowing down the fastpath
of all the other common scheduler functions, for the sake of a rarely
used (and broken ...) API: yield. And note that an rbtree walk is not
slow at all - if you are yielding frequently it's probably all cached.
Ingo
next prev parent reply other threads:[~2008-02-21 6:04 UTC|newest]
Thread overview: 25+ messages / expand[flat|nested] mbox.gz Atom feed top
2008-02-21 5:33 Make yield_task_fair more efficient Balbir Singh
2008-02-21 6:04 ` Ingo Molnar [this message]
2008-02-21 6:51 ` Balbir Singh
2008-02-21 7:07 ` Ingo Molnar
2008-02-21 7:39 ` Balbir Singh
2008-02-21 8:43 ` Peter Zijlstra
2008-02-21 8:50 ` Balbir Singh
2008-02-21 9:04 ` Ingo Molnar
2008-02-21 9:31 ` Balbir Singh
2008-02-21 9:42 ` Ingo Molnar
2008-02-21 9:44 ` Balbir Singh
2008-02-21 9:43 ` Peter Zijlstra
2008-02-21 9:42 ` Balbir Singh
2008-02-21 10:01 ` Peter Zijlstra
2008-02-21 10:07 ` Balbir Singh
2008-02-21 11:12 ` Peter Zijlstra
2008-02-21 11:27 ` Balbir Singh
2008-02-21 20:38 ` Jens Axboe
2008-02-21 20:55 ` Jens Axboe
2008-02-22 3:27 ` Balbir Singh
2008-02-21 10:17 ` Balbir Singh
2008-02-21 12:02 ` Mike Galbraith
2008-02-21 12:06 ` Mike Galbraith
2008-02-21 13:29 ` Balbir Singh
2008-02-21 14:38 ` Jörn Engel
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