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

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On July 15, 2016 6:59:56 AM PDT, Peter Zijlstra [off-list ref] wrote:

On Fri, Jul 15, 2016 at 01:52:48PM +0000, Topi Miettinen wrote:

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On 07/15/16 12:43, Peter Zijlstra wrote:

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On Fri, Jul 15, 2016 at 01:35:47PM +0300, Topi Miettinen wrote:

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Hello,

There are many basic ways to control processes, including

capabilities,

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cgroups and resource limits. However, there are far fewer ways to

find out

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useful values for the limits, except blind trial and error.

This patch series attempts to fix that by giving at least a nice

starting

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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

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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.

One reason is to catch a malfunctioning process rather than dragging the whole system down with it.  It could also be useful for development.
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