High CPU and Semaphores Usage by Apache HTTPD with SiteMinder

Solution Verified - Updated -


  • In Prod server we are experiencing issue with Apache. Even when we gracefully stop apache, it leaves semaphore processes behind, so when Apache starts, it will start spawning 100+ threads, causing CPU high load. We have identical Apache setup in our pre-prod environment and it does not have any such issues. We would like to know why Semaphore process is not removed when we stop apache.


  • Red Hat Enterprise Linux (RHEL)
  • Red Hat Software Collections (RHSCL)
  • Red Hat JBoss Core Services (JBCS)
  • Apache Web Server (httpd)

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