Apache stops serving requests when connections increase

Posted by Gunjan on Server Fault See other posts from Server Fault or by Gunjan
Published on 2012-08-31T10:10:20Z Indexed on 2012/08/31 15:41 UTC
Read the original article Hit count: 183

Filed under:

apache2

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php

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load

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scalability

The values for MaxClients, ServerLimit etc parameters are quite high (4000). Available RAM on the server is high too (~8G). Load average remains below 1 on a 24 core CPU. But when the number of visitors on the website increase apache just stops serving requests. The apache error log is blank and access log shows no more requests coming in.

Restarting apache makes it work again until the number of requests increases again.

Any ideas where to start looking?

UPDATE Getting the below errors in apache error log on running it with LogLevel Debug [info] server seems busy, (you may need to increase StartServers, or Min/MaxSpareServers), spawning 32 children, there are 479 idle, and 1027 total children

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