Re: [PATCH] Make swap accounting default behavior configurable

Daisuke Nishimura
2010-11-18T08:55:48Z

On Thu, 18 Nov 2010 09:23:32 +0100
Michal Hocko <mhocko@suse.cz> wrote:

> On Wed 17-11-10 12:28:01, Daisuke Nishimura wrote:
> > On Tue, 16 Nov 2010 17:12:25 -0800
> > Andrew Morton <akpm@linux-foundation.org> wrote:
> >
> > > On Wed, 17 Nov 2010 09:23:39 +0900 Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp> wrote:
> > >
> > > > > >
> > > > > > diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
> > > > > > index ed45e98..14eafa5 100644
> > > > > > --- a/Documentation/kernel-parameters.txt
> > > > > > +++ b/Documentation/kernel-parameters.txt
> > > > > > @@ -2385,6 +2385,9 @@ and is between 256 and 4096 characters. It is defined in the file
> > > > > > improve throughput, but will also increase the
> > > > > > amount of memory reserved for use by the client.
> > > > > >
> > > > > > + swapaccount [KNL] Enable accounting of swap in memory resource
> > > > > > + controller. (See Documentation/cgroups/memory.txt)
> > > > >
> > > > > So we have swapaccount and noswapaccount. Ho hum, "swapaccount=[1|0]"
> > > > > would have been better.
> > > > >
> > > > I suggested to keep "noswapaccount" for compatibility.
> > > > If you and other guys don't like having two parameters, I don't stick to
> > > > the old parameter.
> > > >
> > >
> > > Yes, we're stuck with the old one now.
> > >
> > > But we should note that "foo=[0|1]" is superior to "foo" and "nofoo".
> > > Even if we didn't initially intend to add "nofoo".
> > >
> > I see.
> >
> > Michal-san, could you update your patch to use "swapaccount=[1|0]" ?
>
> I have noticed that Andrew has already taken the last version of the
> patch for -mm tree. Should I still rework it to change swapaccount to
> swapaccount=0|1 resp. true|false?
>
It's usual to update a patch into more sophisticated one while it is in -mm tree.
So, I think you'd better to do it(btw, I prefer 0|1 to true|false.
Reading kernel-parameters.txt, 0|1 is more commonly used.).

Thanks,
Daisuke Nishimura.