Apache 2.4 list prefork directive values from command line

Question

I am unable to find values of MPM Prefork directives like MaxRequestWorkers/MaxSpareThreads etc in my config file. Is there a way to list these values from command line?

-bash-4.2# httpd -v
Server version: Apache/2.4.23 (Amazon)

-bash-4.2# httpd -V
Server version: Apache/2.4.23 (Amazon)
Server built:   Jul 29 2016 21:42:17
Server's Module Magic Number: 20120211:61
Server loaded:  APR 1.5.1, APR-UTIL 1.4.1
Compiled using: APR 1.5.1, APR-UTIL 1.4.1
Architecture:   64-bit
Server MPM:     prefork
  threaded:     no
    forked:     yes (variable process count)
Server compiled with....
 -D APR_HAS_SENDFILE
 -D APR_HAS_MMAP
 -D APR_HAVE_IPV6 (IPv4-mapped addresses enabled)
 -D APR_USE_SYSVSEM_SERIALIZE
 -D APR_USE_PTHREAD_SERIALIZE
 -D SINGLE_LISTEN_UNSERIALIZED_ACCEPT
 -D APR_HAS_OTHER_CHILD
 -D AP_HAVE_RELIABLE_PIPED_LOGS
 -D DYNAMIC_MODULE_LIMIT=256
 -D HTTPD_ROOT="/etc/httpd"
 -D SUEXEC_BIN="/usr/sbin/suexec"
 -D DEFAULT_PIDLOG="/var/run/httpd/httpd.pid"
 -D DEFAULT_SCOREBOARD="logs/apache_runtime_status"
 -D DEFAULT_ERRORLOG="logs/error_log"
 -D AP_TYPES_CONFIG_FILE="conf/mime.types"
 -D SERVER_CONFIG_FILE="conf/httpd.conf"

PS: I have posted it on SuperUser as well. I am not sure which one is the right place.

Answer 1

1. you will never find MaxSpareThreads because prefork is not threaded, so it should be **MaxSpareServers**
2. Not from the command line, you need to "cat" your main configuration file, or whereever your distro has placed them (httpd.conf or apache.conf or mpm.conf?)
3. If you have mod_info you can "curl" your server for its information and parse/read the settings from it, that's the closest thing to get that info from command line you will probably find. There you will see a section called Module name: prefork.c and after some text something that says "Current Configuration:" which shows your actual mpm settings. (note: mod_info should not be publicaly available in your server to anyone that accesses it since it practically reveals your whole configuration).

Should you need further info about how prefork is/should be configured you can check it at the official docs about mpm prefork

Note: I would not recommend prefork anways, go for event and if it is because mod_php, ditch it in favour of php-fpm.