By default, the httpd-mpm.conf file which contains configuration (inside <IfModule mpm_worker_module> section) is used to handle any memory leak caused by httpd child process. The default value of MaxConnectionsPerChild should be such that the leaked memory is released by gracefully restarting the httpd child process without impacting the user.There is a possibility, depending on system load and limited available system memory resource, the default number may not be accurate to release the leaked memory at timely fashion. This causes the system services to stop responding as sufficient memory is not available.
You can use various system commands (for example, top) to view the overall system resource and memory consumption by httpd process.
Workaround: Reduce the MaxConnectionsPerChild value to a lower value and view the results. You might have to follow the trial and error method to arrive at an ideal MaxConnectionsPerChild value for the environment. For more information, see httpd.apache.org.
NOTE:Do not reduce the MaxConnectionsPerChild value to a very low value as it can impact user activity.