[squid-users] Is Squid can shutdown unused idle redirector's children?

[Yuri Voinov]

http://i58.tinypic.com/rsqwxh.png

0 shutting down. Always.

During nights and weekends.

16.02.15 19:13, Eliezer Croitoru пишет:
> Hey Yuri,
>
> There are couple sides and side-effects to the issue you describe.
> If it's OK with you I will for a sec look aside squid and the helpers 
> code to another issue in Computer Science.
>
> Let say we are running some server\software which it's purpose is to 
> calculate the distance from point X to Y for a user.(A real world 
> existing software which was written for DOS)
> Since this piece of software size is about 50kB the user never 
> experienced any issues with this particular software.
> The issues came in when the user needed to run some complex 
> calculations on a big list of points from a map.
> From what I have seen in the past a 133Mhz CPU should take the load, 
> and indeed did not had any issues working with a big set of points 
> what so ever was thrown at it.
> The main complexity with this piece of software was when the 
> calculations needed to be more complex and turned from X to Y to "from 
> X to Y considering A B C D E F G H I".
> Then the CPU got hogged a bit and there for the calculation took a bit 
> longer then expected by the user.
> Just as a side note this DOS system didn't had any SWAP at all.
> This software is still in use since about 198x until these days with 
> no SWAP at all while the calculations are being made daily by lots of 
> users around my country.
> From Computer Science point of view this piece of software is one of 
> the most efficient ever existed on earth and while it was written for 
> DOS it is still efficient enough to support many other systems around 
> the world.
>
> Wouldn't any developer want to write a code in this level?? I believe 
> and know that any developer strives to write a software that will use 
> the available system resources efficiently.
> But for any developer there is a point which he sees how his knowledge 
> alone might not be enough to make a simple piece of software run as 
> smooth and as efficient as this simple DOS software.
> I have never asked the creator of this DOS program how much efforts it 
> took from him and his companions to write such a great piece of ART 
> which is one of a kind, it was not because he is dead or something 
> similar but since I understand it's a complex task which I am not 
> trying to mimic.
>
> And back to squidguard, I myself have tried to understand why it uses 
> so much ram and other resources which should have not being occupied 
> at all.
> Eventually I have written my own version which is a mimic for 
> squidguard basic filtering logic.
> I have seen this behavior you do see and I have couple of times tried 
> to at least make something better then it is now.
> The task was not simple but my idea after lots of time of thinking was 
> to separate most of the logic outside of the url_rewrite interface.
>
> I would not just try to solve the issue as "60 processes Absolutely 
> idle", this might not be the issue in hands at all!
> This conclusion can divert you from the real issue in this situation.
>
> If you are up to the task to share(publicly is not a must) a top 
> snapshot of the machine at midnight while you see the issue I will 
> gladly be more then happy to try and understand the issue in hands.
> I am pretty sure that the command "top -n1 -b" should work in any unix 
> system I have seen until today.
>
> Do you have access to this squid machine cache manager interface?
>
> Eliezer
>
> On 12/02/2015 20:01, Yuri Voinov wrote:
>> Hi gents,
>>
>> subj.
>>
>> And, of course - question. How to do that? I've don't seen this, if it
>> exists.
>>
>> For example, for this config stub:
>>
>> url_rewrite_program /usr/local/bin/squidGuard -c
>> /usr/local/squidGuard/squidGuard.conf
>> url_rewrite_children 100 startup=0 idle=1 concurrency=0
>>
>> After daily activity, at midnight, still remain near 60 processes.
>> Absolutely idle.
>>
>> So, why?
>>
>> WBR, Yuri
>
>