Messages in this thread |  | | | Date | Sat, 21 May 2011 00:03:14 +0200 | | From | torbenh <> | | Subject | Re: [rfc] Ignore Fsync Calls in Laptop_Mode |
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On Fri, May 20, 2011 at 06:40:49PM +0200, D. Jansen wrote: > On Fri, May 20, 2011 at 5:28 PM, <Valdis.Kletnieks@vt.edu> wrote: > > On Thu, 19 May 2011 15:34:46 +0200, Dennis Jansen said: > > > >> Testing: > >> I've been using this workaround on my netbook for over six months now. > >> It works as expected for me with all software in a Ubuntu 9.10 > >> environment and saves me at least 0.5 Watt or roughly 10 % battery > >> time - without destroying my hard disk. I have seen no negative side > >> effects. > > > > How much destructive testing did you do? In the 6 months, how many times did > > the system crash (or had the battery pulled out, or whatever) while large > > amounts of data were still pending after apps thought they were fsync'ed? How > > much crash testing was done against apps that use fsync for ordering or > > correctness reasons? > > I don't see the point in verifying the obvious. Of course applications > that rely on fsync will lose data. > The real problem comes with ordering correctness, which could actually > _destroy previous data_ as well. > In my scenario (office applications, browsing) I have not hit such a problem.
how about making fsync block until the harddisk spins up ? this would also enable you to detect these apps you wouldnt be using in laptop mode anyways ?
-- torben Hohn -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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