Sign up ×
Server Fault is a question and answer site for system and network administrators. It's 100% free, no registration required.

Our server is forced to restart sometimes because some users (not all) could start more zombie suphp defunct processes than allowed through the RLIMIT_NPROC / ulimit -u statement.

How is that possible? Is there a known bug or something similar? And do you know how I could handle that?

I'm running CentOS 5.8 with Apache 2.2.3

Thanks. Best regards, John

share|improve this question
What process is the parent of these defunct processes? – David Schwartz Mar 20 '13 at 13:59
Hm, good question. Could I figure that out backwards? Where is this logged? – John Brunner Mar 20 '13 at 14:29
don't really know which parent processes our users run, but this rlimit_nproc statement is declared for every user (in apache config), in the range of 20-50, and some user could exceed that limit, and other user have troubles to run under 10 processes. it's not really reliable – John Brunner Mar 20 '13 at 14:41
I've made an c script which produces 50,000 zombie processes. even if my ulimit -u statement is configured to 50,000... there are just exactly 32,354 processes (not more). when I lower down the ulimit it works finde (ulimit -> 20,000 zombie processes -> 20,001)... i can't figure out why it works sometimes and sometimes not – John Brunner Mar 20 '13 at 15:49

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Browse other questions tagged or ask your own question.