Have sane default values for cpusets
in [Kernel]
|
Prev: [PATCH] remove bogus #ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT for debug_kmap_atomic()
Next: [pm] resume from s3 oops? (last checked on rc6)
From: Dhaval Giani on 12 May 2010 09:50 On Wed, May 12, 2010 at 3:40 PM, Peter Zijlstra <peterz(a)infradead.org> wrote: > On Wed, 2010-05-12 at 15:05 +0200, Dhaval Giani wrote: >> Where cpusets goes wrong is to have a *no* default values. > > It has a default, empty is still a valid value. > Well, it is still not sane. And in the part you snipped, I did mention, >> do we enforce a policy to have sane defaults >> for subsystems if they prevent attaching "regular" tasks by default. And to add to it, a sane default can be defined as one, where a task can be attached to a cgroup on creation without changing any other parameter. Dhaval -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
From: Peter Zijlstra on 12 May 2010 09:50 On Wed, 2010-05-12 at 15:05 +0200, Dhaval Giani wrote: > Where cpusets goes wrong is to have a *no* default values. It has a default, empty is still a valid value. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
From: Dhaval Giani on 12 May 2010 10:20 [Please do *NOT* drop the cc list] On Wed, May 12, 2010 at 4:11 PM, James Kosin <jkosin(a)intcomgrp.com> wrote: > On 5/12/2010 9:50 AM, Dhaval Giani wrote: >> On Wed, May 12, 2010 at 3:40 PM, Peter Zijlstra <peterz(a)infradead.org> wrote: >>> On Wed, 2010-05-12 at 15:05 +0200, Dhaval Giani wrote: >>>> Where cpusets goes wrong is to have a *no* default values. >>> >>> It has a default, empty is still a valid value. >>> >> >> Well, it is still not sane. And in the part you snipped, I did mention, >> >>>> do we enforce a policy to have sane defaults >>>> for subsystems if they prevent attaching "regular" tasks by default. >> >> And to add to it, a sane default can be defined as one, where a task >> can be attached to a cgroup on creation without changing any other >> parameter. >> >> Dhaval > > By keeping the insane policy, we force everyone to properly setup to > sane defaults. �By automatically inheriting the defaults, we would be > introducing the possibility of a lazy programmer forgetting to setup the > proper defaults for their application which may need different values > than the inherited settings. �This would lead to ensuing chaos eventually. Nope. Not really. What you are saying is that an application programmer who wants to just use memory cgroups should also care about cpusets and just about countless other cgroup subsystems that can exist. A lazy programmer not setting up a sane value for what he cares about will see abnormal execution of his application and be able to fix it. You are talking about moving the burden of setup to the people who should be least concerned about it. Dhaval -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
From: James Kosin on 12 May 2010 10:20 On 5/12/2010 9:50 AM, Dhaval Giani wrote: > On Wed, May 12, 2010 at 3:40 PM, Peter Zijlstra <peterz(a)infradead.org> wrote: >> On Wed, 2010-05-12 at 15:05 +0200, Dhaval Giani wrote: >>> Where cpusets goes wrong is to have a *no* default values. >> >> It has a default, empty is still a valid value. >> > > Well, it is still not sane. And in the part you snipped, I did mention, > >>> do we enforce a policy to have sane defaults >>> for subsystems if they prevent attaching "regular" tasks by default. > > And to add to it, a sane default can be defined as one, where a task > can be attached to a cgroup on creation without changing any other > parameter. > > Dhaval By keeping the insane policy, we force everyone to properly setup to sane defaults. By automatically inheriting the defaults, we would be introducing the possibility of a lazy programmer forgetting to setup the proper defaults for their application which may need different values than the inherited settings. This would lead to ensuing chaos eventually. James -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
From: Peter Zijlstra on 12 May 2010 10:30
On Wed, 2010-05-12 at 16:13 +0200, Dhaval Giani wrote: > What you are saying is that an application > programmer who wants to just use memory cgroups should also care about > cpusets and just about countless other cgroup subsystems that can > exist. That's exactly what he says if he mounts them together. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/ |