RE: Apache process crashes, utilizing high memory

[Arnav Garg <arnav.garg@xxxxxxxxxxxxx>]

Hi Nigel,

 

Thanks for your prompt reply.

Can you please help me in clarifying some of my doubts?

1.       What is the significance of setting MaxConnectionsPerChild to a value between 1-100 ?

2.       What are the possible reasons for not setting MaxConnectionsPerChild to a high value, greater than 100 ?

 

Thanks & Regards

Arnav Garg

 

From: Nigel B. Peck [mailto:nigelbpeck@xxxxxxxxx]
Sent: Wednesday, August 21, 2019 11:51 AM
To: users@xxxxxxxxxxxxxxxx
Subject: Re: [users@httpd] Apache process crashes, utilizing high memory

 

On Mon, 19 Aug 2019 at 11:24 pm, Arnav Garg <arnav.garg@xxxxxxxxxxxxx> wrote:

Hi All,

 

I have an apache web server(v2.4) + ckan (v2.7.2) running in a docker container.
In our scenario, CKAN is being hit with large number of requests at certain intervals (like 10 requests/sec). Then after a certain period of time, the memory consumption tends to increase towards it's threshold value.

After a certain interval/time, if we access the home page of ckan at https://url-address/ckan with large number of request(Using Jmeter), the memory usage of the Apache process keeps on increasing and ultimately the process crashes and does not work properly.

As a quick remedy for this, restarting the docker container reduces the memory usage.

My concern is that, are there any set of conditions/parameters in Apache Webserver that needs to be taken care of to prevent this behavior. for eg: MaxConnectionPerChild or any other Parameter? Or is there any way to limit the memory consumption of Apache web server?

Some of the values set in apache2.conf are:

1.       Timeout 300

2.       KeepAlive On

3.       MaxKeepAliveRequests 100

4.       KeepAliveTimeout 5

Also /apache2/mods-enabled/mpm_event.conf consists of the following parameters and values:

1.       StartServers                     2

2.       MinSpareThreads           25

3.       MaxSpareThreads          75

4.       ThreadLimit                     64

5.       ThreadsPerChild             25

6.       MaxRequestWorkers     150

7.       MaxConnectionsPerChild   0

Thanks & Regards
Arnav Garg

 

Setting MaxConnectionsPerChild to something not too high (100 as a temporary fix?) should avoid you needing to restart your Docker container, sounds like you probably have a memory leak in your application that needs fixing.

 

Nigel B. Peck

 

Web Technologies and Linux Server Admin Mentor

https://codementor.io/nigelbpeck

 

 

 

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