Hi Nigel, Thanks for your prompt reply, I had one more doubt:
While keeping the value of MaxConnectionPerChild to 1, my memory consumption do not increase as rapidly as it was earlier when it was set to 0. Here are the statistics: My initial memory was : USER PID %CPU %MEM VSZ RSS TTY STAT START TIME COMMAND ckan-ap+ 12793 0.2 0.0 304068 6096 ? Sl 06:35 0:00 ckan_default -k start ckan-ap+ 12794 0.2 0.0 304068 6104 ? Sl 06:35 0:00 ckan_default -k start ckan-ap+ 12795 0.0 0.0 304076 6104 ? Sl 06:35 0:00 ckan_default -k start ckan-ap+ 12796 0.0 0.0 304068 6104 ? Sl 06:35 0:00 ckan_default -k start After firing 105 requests/per sec for 5 times with a Thread delay of 360 milliseconds using Jmeter. The memory after firing the requests Case 1: When I used to have MaxConnectionPerChild “0”: The output observed using “top” command: USER PID %CPU %MEM VSZ RSS TTY STAT START TIME COMMAND ckan-ap+ 12793 14.4 1.5 1444920 124880 ? Sl 06:35 0:13 ckan_default -k start ckan-ap+ 12794 14.0 1.4 1441080 119300 ? Sl 06:35 0:13 ckan_default -k start ckan-ap+ 12795 14.8 1.5 1442120 120724 ? Sl 06:35 0:14 ckan_default -k start ckan-ap+ 12796 14.5 1.5 1442616 120904 ? Sl 06:35 0:13 ckan_default -k start Case 2: When MaxConnection PerChild was set to “1”. USER PID %CPU %MEM VSZ RSS TTY STAT START TIME COMMAND ckan-ap+ 13448 13.6 1.3 845368 108904 ? Sl 06:39 0:11 ckan_default -k start ckan-ap+ 13449 11.6 1.3 845376 104560 ? Sl 06:39 0:09 ckan_default -k start ckan-ap+ 13450 11.7 1.2 844608 102696 ? Sl 06:39 0:09 ckan_default -k start ckan-ap+ 13451 11.8 1.2 844344 102392 ? Sl 06:39 0:09 ckan_default -k start The value highlighted in yellow remains almost the same or nearby when the performance testing was done for 2 hours. Case 3: When MaxConnectionPerChild was set to “100”. Output: same as Case 1. Doubt: if you can please let us know on the performance or any side effects if I keep the value of MaxConnectionPerChild as 0 , 1 and 100? Thanks & Regards Arnav >> I’m suggesting 100 because it seems you have a memory leak, so looking to >> make sure they are restarted before that takes up too much memory. The cost >> is the overhead of spawning a new process every X number of connections. >> If you set it higher then your memory leak will have more effect. Will there be any performance impact From: Nigel B. Peck [mailto:nigelbp...@gmail.com] Sent: Thursday, August 22, 2019 11:10 AM To: users@httpd.apache.org Subject: Re: [users@httpd] Apache process crashes, utilizing high memory On Thu, 22 Aug 2019 at 12:02 am, Arnav Garg <arnav.g...@india.nec.com<mailto:arnav.g...@india.nec.com>> wrote: 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 ? It specifies the number of connections that a child process will serve before being closed and a new one spawned. Having it as 0 means there’s no limit so they just keep running. I’m suggesting 100 because it seems you have a memory leak, so looking to make sure they are restarted before that takes up too much memory. The cost is the overhead of spawning a new process every X number of connections. If you set it higher then your memory leak will have more effect. Best thing is to set it and then monitor and load test the server to get data to guide decisions on what works for your situation. And identify and fix the memory leak :) Hope that helps. Nigel Web Technologies and Linux Admin Mentor https://codementor.io/nigelbpeck ________________________________ The contents of this e-mail and any attachment(s) are confidential and intended for the named recipient(s) only. It shall not attach any liability on the originator or NECTI or its affiliates. Any views or opinions presented in this email are solely those of the author and may not necessarily reflect the opinions of NECTI or its affiliates. Any form of reproduction, dissemination, copying, disclosure, modification, distribution and / or publication of this message without the prior written consent of the author of this e-mail is strictly prohibited. If you have received this email in error please delete it and notify the sender immediately.
