Re: [RFC][PATCH] allow "unlimited" limit value.

[Balbir Singh <balbir-23VcF4HTsmIX0ybBhKVfKdBPR1lH4CV8@public.gmane.org>]

KAMEZAWA Hiroyuki wrote:
> On Tue, 25 Sep 2007 16:19:18 +0530
> Balbir Singh <balbir-23VcF4HTsmIX0ybBhKVfKdBPR1lH4CV8@public.gmane.org> wrote:
> 
>> Hi, Kamezawa-San,
>>
> Hi,
> 
>> Your changes make sense, but not CLUI (Command Line Usage) sense.
>> 1. The problem is that when we mix strings with numbers, tools that
>>    parse/use get confused and complicated
> yes, maybe.
> 
>> 2. ULONGLONG_MAX is a real limit, there is no such thing as unlimited.
>>    If the user does ever go beyond ULONGLONG_MAX, we will limit him :-)
>>
> Oh. res_counter.c  uses LONGLONG_MAX as default value.
> need fix ? or intended ?

Pavel do you remember why LONG was chosen instead of ULONG?

> And okay there is no "unlimited" state.
> 
>> Having said that, I do wish to have a more intuitive interface for
>> users. May be a perl/python script to hide away the numbers game
>> from the users. What do you think?
>>
> I agree with you that perl/python script can hide details. but they need knowledge
> about the maximum value, which is given as default value.
> 
> In short, what I want is some value like RLIM_INFINITY in ulimit.
> 

I like the idea of RLIM_INFINITY and how ulimit as a tool shows
a value. I guess we need something like RES_COUNTER_LIMIT_MAX
and the user tool can show the limit as maximum. We could also
define a special number, RES_COUNTER_LIMIT_INFINITY, such that
containers will not enforce limits when the limit is set to
this value.

> 
> Because it seems that res_counter.c will be used for other resouce control purpose,
> I thought some generic way (value) to know/specify "the maximum value" is helpful for
> all resource controller interface.
> 
> If there is an concensus that treaing ULONGLONG_MAX as default, it's ok.
> 

When I worked on the first version of res_counters, I used 0 to indicate
unlimited. When Pavel posted his version, I think derived from
beancounters, we did not want to have unlimited containers, so he used
the maximum value

> Thanks,
> -Kame
> 

Thanks for looking into this,

-- 
	Warm Regards,
	Balbir Singh
	Linux Technology Center
	IBM, ISTL