Re: [PATCH 00/14] Present useful limits to user (v2)

From: Peter Zijlstra <peterz@infradead.org>
To: Topi Miettinen <toiwoton@gmail.com>
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Subject: Re: [PATCH 00/14] Present useful limits to user (v2)
Date: Fri, 15 Jul 2016 15:59:56 +0200	[thread overview]
Message-ID: <20160715135956.GA3115@twins.programming.kicks-ass.net> (raw)
In-Reply-To: <28b4b919-4f50-d9f6-c5e1-d1e92ea1ba1c@gmail.com>

On Fri, Jul 15, 2016 at 01:52:48PM +0000, Topi Miettinen wrote:
> On 07/15/16 12:43, Peter Zijlstra wrote:
> > On Fri, Jul 15, 2016 at 01:35:47PM +0300, Topi Miettinen wrote:
> >> Hello,
> >>
> >> There are many basic ways to control processes, including capabilities,
> >> cgroups and resource limits. However, there are far fewer ways to find out
> >> useful values for the limits, except blind trial and error.
> >>
> >> This patch series attempts to fix that by giving at least a nice starting
> >> point from the highwater mark values of the resources in question.
> >> I looked where each limit is checked and added a call to update the mark
> >> nearby.
> > 
> > And how is that useful? Setting things to the high watermark is
> > basically the same as not setting the limit at all.
> 
> What else would you use, too small limits?

That question doesn't make sense.

What's the point of setting a limit if it ends up being the same as
no-limit (aka unlimited).

If you cannot explain; and you have not so far; what use these values
are, why would we look at the patches.

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