Messages in this thread | | | Date | Fri, 14 Oct 2011 00:14:40 +0400 | From | Glauber Costa <> | Subject | Re: [PATCH v7 0/8] Request for inclusion: tcp memory buffers |
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On 10/14/2011 12:12 AM, David Miller wrote: > From: Glauber Costa<glommer@parallels.com> > Date: Fri, 14 Oct 2011 00:05:58 +0400 > >> Also, I kind of dispute the affirmation that !cgroup will encompass >> the majority of users, since cgroups is being enabled by default by >> most vendors. All systemd based systems use it extensively, for >> instance. > > I will definitely advise people against this, since the cost of having > this on by default is absolutely non-trivial. > > People keep asking every few releases "where the heck has my performance > gone" and it's because of creeping features like this. This socket > cgroup feature is a prime example of where that kind of stuff comes > from. > > I really get irritated when people go "oh, it's just one indirect > function call" and "oh, it's just one more pointer in struct sock" > > We work really hard to _remove_ elements from structures and make them > smaller, and to remove expensive operations from the fast paths. > > It might take someone weeks if not months to find a way to make a > patch which compensates for the extra overhead your patches are adding. > > And I don't think you fully appreciate that.
Let's focus on this: Are you happy, or at least willing to accept, an approach that keep things as they were with cgroups *compiled out*, or were you referring to not in use == compiled in, but with no users?
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