Quando executo o comando ps aux , vejo muitas entradas /usr/sbin/apache2 -k start (na máquina Ubuntu) e /usr/sbin/httpd -k start (In Centos). Eu li em algum lugar que cada uma dessas entradas é um processo apache, que é criado de antemão para estar pronto para o pedido futuro para o servidor.
Então, pelo que entendi, cada um desses processos do apache é para atender à solicitação http e ela é desativada depois que o trabalho é concluído, e outros processos serão criados para se preparar para outras solicitações futuras.
O que não estou claro é que cada processo apache irá servir um pageload ou um hit? (Como cada pageload pode ter algumas dezenas de acertos).
Estou fazendo esta pergunta porque estou vendo dois comportamentos diferentes do Ubuntu e do Centos. Eu estou mais familiarizado com o Ubuntu, e minhas máquinas Ubuntu nunca encontraram problemas de carga alta quando eu tenho um monte de acessos a páginas inexistentes (quando eu digo páginas inexistentes, isso significa que os arquivos não existe no servidor e não é reescrito para um arquivo php por um arquivo .htaccess)
No entanto, recentemente tenho que gerenciar um servidor Centos. Vejo alguns robôs ruins jogando de 20 a 30 hits em páginas inexistentes em um ou dois segundos, e toda vez que isso acontece, a carga média é muito alta, e também vejo um monte de /usr/sbin/httpd -k start de entradas de ps aux comando.
Então eu acho que o Centos usa um processo httpd para cada hit, e no Ubuntu cada processo do Apache pode ser usado para vários hits. Isso é uma especulação correta? Se isso estiver correto, acho que o Centos é muito ineficiente comparado ao Ubuntu.
Alguém poderia esclarecer esses pontos para que eu possa ver o que estou perdendo?
Muito obrigado!
Atualização 1 :
Eu também vejo outra diferença: Quando eu abro um url de máquinas Ubuntu, um processo /usr/bin/php5-cgi é criado, e este processo ainda está lá por muito tempo (horas) mesmo que o pageload seja concluído dentro de 1-2 segundos . Então eu acho que este processo de php está segurando algumas informações de cache para que ele possa ser usado para servir a próxima requisição de página (eu não vejo um novo processo de /usr/bin/php5-cgi quando eu continuo navegando para outra página)
Mas na máquina Centos, quando visito uma página, se tiver sorte, posso ver um processo /opt/cpanel/ea-php56/root/usr/bin/php-cgi , e esse processo quase desaparece imediatamente após 1-2 segundos
Atualização 2
Aqui está o conteúdo do /etc/apache2/apache2.conf (Ubuntu)
# This is the main Apache server configuration file. It contains the
# configuration directives that give the server its instructions.
# See http://httpd.apache.org/docs/2.4/ for detailed information about
# the directives and /usr/share/doc/apache2/README.Debian about Debian specific
# hints.
#
#
# Summary of how the Apache 2 configuration works in Debian:
# The Apache 2 web server configuration in Debian is quite different to
# upstream's suggested way to configure the web server. This is because Debian's
# default Apache2 installation attempts to make adding and removing modules,
# virtual hosts, and extra configuration directives as flexible as possible, in
# order to make automating the changes and administering the server as easy as
# possible.
# It is split into several files forming the configuration hierarchy outlined
# below, all located in the /etc/apache2/ directory:
#
# /etc/apache2/
# |-- apache2.conf
# | '-- ports.conf
# |-- mods-enabled
# | |-- *.load
# | '-- *.conf
# |-- conf-enabled
# | '-- *.conf
# '-- sites-enabled
# '-- *.conf
#
#
# * apache2.conf is the main configuration file (this file). It puts the pieces
# together by including all remaining configuration files when starting up the
# web server.
#
# * ports.conf is always included from the main configuration file. It is
# supposed to determine listening ports for incoming connections which can be
# customized anytime.
#
# * Configuration files in the mods-enabled/, conf-enabled/ and sites-enabled/
# directories contain particular configuration snippets which manage modules,
# global configuration fragments, or virtual host configurations,
# respectively.
#
# They are activated by symlinking available configuration files from their
# respective *-available/ counterparts. These should be managed by using our
# helpers a2enmod/a2dismod, a2ensite/a2dissite and a2enconf/a2disconf. See
# their respective man pages for detailed information.
#
# * The binary is called apache2. Due to the use of environment variables, in
# the default configuration, apache2 needs to be started/stopped with
# /etc/init.d/apache2 or apache2ctl. Calling /usr/bin/apache2 directly will not
# work with the default configuration.
# Global configuration
#
#
# ServerRoot: The top of the directory tree under which the server's
# configuration, error, and log files are kept.
#
# NOTE! If you intend to place this on an NFS (or otherwise network)
# mounted filesystem then please read the Mutex documentation (available
# at <URL:http://httpd.apache.org/docs/2.4/mod/core.html#mutex>);
# you will save yourself a lot of trouble.
#
# Do NOT add a slash at the end of the directory path.
#
#ServerRoot "/etc/apache2"
#
# The accept serialization lock file MUST BE STORED ON A LOCAL DISK.
#
Mutex file:${APACHE_LOCK_DIR} default
#
# PidFile: The file in which the server should record its process
# identification number when it starts.
# This needs to be set in /etc/apache2/envvars
#
PidFile ${APACHE_PID_FILE}
#
# Timeout: The number of seconds before receives and sends time out.
#
Timeout 300
#
# KeepAlive: Whether or not to allow persistent connections (more than
# one request per connection). Set to "Off" to deactivate.
#
KeepAlive On
#
# MaxKeepAliveRequests: The maximum number of requests to allow
# during a persistent connection. Set to 0 to allow an unlimited amount.
# We recommend you leave this number high, for maximum performance.
#
MaxKeepAliveRequests 100
#
# KeepAliveTimeout: Number of seconds to wait for the next request from the
# same client on the same connection.
#
KeepAliveTimeout 5
# These need to be set in /etc/apache2/envvars
User ${APACHE_RUN_USER}
Group ${APACHE_RUN_GROUP}
#
# HostnameLookups: Log the names of clients or just their IP addresses
# e.g., www.apache.org (on) or 204.62.129.132 (off).
# The default is off because it'd be overall better for the net if people
# had to knowingly turn this feature on, since enabling it means that
# each client request will result in AT LEAST one lookup request to the
# nameserver.
#
HostnameLookups Off
# ErrorLog: The location of the error log file.
# If you do not specify an ErrorLog directive within a <VirtualHost>
# container, error messages relating to that virtual host will be
# logged here. If you *do* define an error logfile for a <VirtualHost>
# container, that host's errors will be logged there and not here.
#
ErrorLog ${APACHE_LOG_DIR}/error.log
#
# LogLevel: Control the severity of messages logged to the error_log.
# Available values: trace8, ..., trace1, debug, info, notice, warn,
# error, crit, alert, emerg.
# It is also possible to configure the log level for particular modules, e.g.
# "LogLevel info ssl:warn"
#
LogLevel warn
# Include module configuration:
IncludeOptional mods-enabled/*.load
IncludeOptional mods-enabled/*.conf
# Include list of ports to listen on
Include ports.conf
# Sets the default security model of the Apache2 HTTPD server. It does
# not allow access to the root filesystem outside of /usr/share and /var/www.
# The former is used by web applications packaged in Debian,
# the latter may be used for local directories served by the web server. If
# your system is serving content from a sub-directory in /srv you must allow
# access here, or in any related virtual host.
<Directory />
Options FollowSymLinks
AllowOverride None
Require all denied
</Directory>
<Directory /usr/share>
AllowOverride None
Require all granted
</Directory>
<Directory /var/www/>
Options Indexes FollowSymLinks
AllowOverride None
Require all granted
</Directory>
#<Directory /srv/>
# Options Indexes FollowSymLinks
# AllowOverride None
# Require all granted
#</Directory>
# AccessFileName: The name of the file to look for in each directory
# for additional configuration directives. See also the AllowOverride
# directive.
#
AccessFileName .htaccess
#
# The following lines prevent .htaccess and .htpasswd files from being
# viewed by Web clients.
#
<FilesMatch "^\.ht">
Require all denied
</FilesMatch>
#
# The following directives define some format nicknames for use with
# a CustomLog directive.
#
# These deviate from the Common Log Format definitions in that they use %O
# (the actual bytes sent including headers) instead of %b (the size of the
# requested file), because the latter makes it impossible to detect partial
# requests.
#
# Note that the use of %{X-Forwarded-For}i instead of %h is not recommended.
# Use mod_remoteip instead.
#
LogFormat "%v:%p %h %l %u %t \"%r\" %>s %O \"%{Referer}i\" \"%{User-Agent}i\"" vhost_combined
LogFormat "%h %l %u %t \"%r\" %>s %O \"%{Referer}i\" \"%{User-Agent}i\"" combined
LogFormat "%h %l %u %t \"%r\" %>s %O" common
LogFormat "%{Referer}i -> %U" referer
LogFormat "%{User-agent}i" agent
# Include of directories ignores editors' and dpkg's backup files,
# see README.Debian for details.
# Include generic snippets of statements
IncludeOptional conf-enabled/*.conf
# Include the virtual host configurations:
IncludeOptional sites-enabled/*.conf
SSLProtocol ALL -SSLv2
SSLCipherSuite ECDHE-RSA-AES256-SHA384:AES256-SHA256:AES256-SHA256:RC4:HIGH:MEDIUM:+TLSv1:+TLSv1.1:+TLSv1.2:!MD5:!ADH:!aNULL:!eNULL:!NULL:!DH:!ADH:!EDH:!AESGCM
# vim: syntax=apache ts=4 sw=4 sts=4 sr noet
Include /etc/phpmyadmin/apache.conf
E aqui está uma parte do /etc/httpd/conf/httpd.conf (Centos) (Outras partes são vhost para domínios, acho que não tem nenhuma informação útil)
# # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # #
#
# !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
# DO NOT EDIT. AUTOMATICALLY GENERATED. USE INCLUDE FILES IF YOU NEED TO MAKE A CHANGE
# !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
#
# Direct modifications to the Apache configuration file WILL be lost upon subsequent
# regeneration of this configuration file, or an Apache update.
#
# To have your modifications retained, you should create/edit administrator-specific
# include files:
#
# /etc/apache2/conf.d/includes/pre_main_global.conf
# /etc/apache2/conf.d/includes/pre_virtualhost_global.conf
# /etc/apache2/conf.d/includes/post_virtualhost_global.conf
#
# # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # #
##################################################
##################################################
#
# cPanel & WHM controlled Apache configuration
#
##################################################
##################################################
Include "/etc/apache2/conf.modules.d/*.conf"
# Administrator locations for safely altering httpd.conf
Include "/etc/apache2/conf.d/includes/pre_main_global.conf"
# These are hard-coded values that are required by cPanel & WHM
PidFile /run/apache2/httpd.pid
User nobody
Group nobody
ExtendedStatus On
LogLevel warn
# You can change this by using WHM, and navigating to the 'Basic cPanel & WHM Setup' -> 'Contact Information' interface.
ServerAdmin [email protected]
# You can change this by using WHM, and navigating to the 'Networking Setup' => 'Change Hostname' interface.
ServerName sv1.howhubs.com
# You can change this by using WHM, and navigating to the 'Apache Configuration' -> 'Global Configuration' interface.
TraceEnable Off
ServerSignature Off
ServerTokens ProductOnly
FileETag None
<Directory "/">
AllowOverride None
Options
</Directory>
StartServers 5
<IfModule prefork.c>
MinSpareServers 5
MaxSpareServers 10
</IfModule>
ServerLimit 256
MaxRequestWorkers 150
MaxConnectionsPerChild 10000
KeepAlive On
KeepAliveTimeout 5
MaxKeepAliveRequests 100
Timeout 300
<IfModule rewrite_module>
# Global DCV Exclude
RewriteEngine on
RewriteCond %{REQUEST_URI} ^/\.well-known/pki-validation/[A-F0-9]{32}\.txt(?:\ Comodo\ DCV)?$ [OR]
RewriteCond %{REQUEST_URI} ^/[0-9]+\..+\.cpaneldcv$
# Exclude proxy subdomains as we need rewrites to capture the DCV requests
RewriteCond %{HTTP_HOST} !^(?:autoconfig|autodiscover|cpanel|cpcalendars|cpcontacts|webdisk|webmail|whm)\.
RewriteRule ^ - [END]
</IfModule>
# You can change this by using WHM, and navigating to the 'Apache Configuration' -> 'DirectoryIndex Priority' interface.
<IfModule dir_module>
DirectoryIndex index.php index.php5 index.php4 index.php3 index.perl index.pl index.plx index.ppl index.cgi index.jsp index.jp index.phtml index.shtml index.xhtml index.html index.htm index.wml Default.html Default.htm default.html default.htm home.html home.htm index.js
</IfModule>
# You can change this by using WHM, and navigating to the 'Apache Configuration' -> 'Memory Usage Restrictions' interface.
# This setting is required by cPanel & WHM in order to provide access to a default webpage when none exists
<Directory "/var/www/html">
Options All
AllowOverride None
Require all granted
</Directory>
# Required cPanel security policy: Disallow remote access to .htaccess, .htpasswd, .user.ini, and php.ini files
<Files ~ "^error_log$">
Order allow,deny
Deny from all
Satisfy All
</Files>
<FilesMatch "^(\.ht(access|passwds?)|\.user\.ini|php\.ini)$">
Require all denied
</FilesMatch>
<IfModule alias_module>
ScriptAliasMatch ^/?controlpanel/?$ /usr/local/cpanel/cgi-sys/redirect.cgi
ScriptAliasMatch ^/?cpanel/?$ /usr/local/cpanel/cgi-sys/redirect.cgi
ScriptAliasMatch ^/?kpanel/?$ /usr/local/cpanel/cgi-sys/redirect.cgi
ScriptAliasMatch ^/?securecontrolpanel/?$ /usr/local/cpanel/cgi-sys/sredirect.cgi
ScriptAliasMatch ^/?securecpanel/?$ /usr/local/cpanel/cgi-sys/sredirect.cgi
ScriptAliasMatch ^/?securewhm/?$ /usr/local/cpanel/cgi-sys/swhmredirect.cgi
ScriptAliasMatch ^/?webmail$ /usr/local/cpanel/cgi-sys/wredirect.cgi
ScriptAliasMatch ^/?webmail/ /usr/local/cpanel/cgi-sys/wredirect.cgi
ScriptAliasMatch ^/?whm/?$ /usr/local/cpanel/cgi-sys/whmredirect.cgi
Alias /bandwidth /usr/local/bandmin/htdocs/
Alias /img-sys /usr/local/cpanel/img-sys/
Alias /java-sys /usr/local/cpanel/java-sys/
Alias /mailman/archives /usr/local/cpanel/3rdparty/mailman/archives/public/
Alias /pipermail /usr/local/cpanel/3rdparty/mailman/archives/public/
Alias /sys_cpanel /usr/local/cpanel/sys_cpanel/
ScriptAlias /cgi-sys /usr/local/cpanel/cgi-sys/
ScriptAlias /mailman /usr/local/cpanel/3rdparty/mailman/cgi-bin/
</IfModule>
# This can be configured in the cPanel 'Leech Protection' interface.
<IfModule rewrite_module>
RewriteEngine on
RewriteMap LeechProtect prg:/usr/local/cpanel/bin/leechprotect
Mutex file:/run/apache2 rewrite-map
</IfModule>
<IfModule mime_module>
TypesConfig conf/mime.types
AddType application/x-compress .Z
AddType application/x-gzip .gz .tgz
AddType text/html .shtml
AddType application/x-tar .tgz
AddType text/vnd.wap.wml .wml
AddType image/vnd.wap.wbmp .wbmp
AddType text/vnd.wap.wmlscript .wmls
AddType application/vnd.wap.wmlc .wmlc
AddType application/vnd.wap.wmlscriptc .wmlsc
# These extensions are used to redirect incoming requests to WHM
AddHandler cgi-script .cgi .pl .plx .ppl .perl
# This is used for custom error documents
AddHandler server-parsed .shtml
</IfModule>
# You can change this by using WHM, and updating the 'Tweak Settings' -> 'System' -> 'Allow server-info' option.
<IfModule status_module>
# This is used by the WHM 'Apache Status' application
<Location /whm-server-status>
SetHandler server-status
Order deny,allow
Deny from all
Allow from 127.0.0.1 ::1
</Location>
</IfModule>
# Required cPanel security policy: disable userdir when mod_ruid2 or mpm_itk or mod_passenger are loaded
<IfModule userdir_module>
UserDir public_html
<IfModule ruid2_module>
UserDir disabled
</IfModule>
<IfModule mpm_itk.c>
UserDir disabled
</IfModule>
<IfModule mod_passenger.c>
UserDir disabled
</IfModule>
</IfModule>
<IfModule log_config_module>
LogFormat "%{Referer}i -> %U" referer
LogFormat "%{User-agent}i" agent
# NOTE: "combined" and "common" are required by WHM
LogFormat "%h %l %u %t \"%r\" %>s %b" common
LogFormat "%h %l %u %t \"%r\" %>s %b \"%{Referer}i\" \"%{User-Agent}i\"" combined
# access_log format can be set in WHM under 'Basic cPanel & WHM Setup'
CustomLog logs/access_log combined
</IfModule>
# The Listen port can be updated using 'Tweak Settings' -> 'System',
# However, if you have any Apache Reserved IPs, then this Tweak setting will
# be ignored. Instead, each IP on your system (excluding Apache Reserved IPs)
# will be listed here.
Listen 0.0.0.0:80
Listen [::]:80
<IfModule ssl_module>
# cipher and protocol directives can be set in WHM under 'Apache Configuration' -> 'Global Configuration'
SSLCipherSuite ECDHE-ECDSA-CHACHA20-POLY1305:ECDHE-RSA-CHACHA20-POLY1305:ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-RSA-AES128-GCM-SHA256:ECDHE-ECDSA-AES256-GCM-SHA384:ECDHE-RSA-AES256-GCM-SHA384:DHE-RSA-AES128-GCM-SHA256:DHE-RSA-AES256-GCM-SHA384:ECDHE-ECDSA-AES128-SHA256:ECDHE-RSA-AES128-SHA256:ECDHE-ECDSA-AES128-SHA:ECDHE-RSA-AES256-SHA384:ECDHE-RSA-AES128-SHA:ECDHE-ECDSA-AES256-SHA384:ECDHE-ECDSA-AES256-SHA:ECDHE-RSA-AES256-SHA:DHE-RSA-AES128-SHA256:DHE-RSA-AES128-SHA:DHE-RSA-AES256-SHA256:DHE-RSA-AES256-SHA:AES128-GCM-SHA256:AES256-GCM-SHA384:AES128-SHA256:AES256-SHA256:AES128-SHA:AES256-SHA:!DSS
SSLProtocol All -SSLv2 -SSLv3
SSLPassPhraseDialog builtin
<IfModule socache_shmcb_module>
SSLUseStapling on
SSLStaplingCache shmcb:/run/apache2/stapling_cache_shmcb(256000)
# Prevent browsers from failing if an OCSP server is temporarily broken.
SSLStaplingReturnResponderErrors off
SSLStaplingErrorCacheTimeout 60
SSLStaplingFakeTryLater off
SSLStaplingResponderTimeout 3
SSLSessionCache shmcb:/run/apache2/ssl_gcache_data_shmcb(1024000)
</IfModule>
<IfModule !socache_shmcb_module>
SSLSessionCache dbm:/run/apache2/ssl_gcache_data_dbm
</IfModule>
SSLSessionCacheTimeout 300
Mutex file:/run/apache2 ssl-cache
SSLRandomSeed startup builtin
SSLRandomSeed connect builtin
# The Listen port can be updated using 'Tweak Settings' -> 'System',
# However, if you have any Apache Reserved IPs, then this Tweak setting will
# be ignored. Instead, each IP on your system (excluding Apache Reserved IPs)
# will be listed here.
Listen 0.0.0.0:443
Listen [::]:443
AddType application/x-x509-ca-cert .crt
AddType application/x-pkcs7-crl .crl
</IfModule>
Include "/etc/apache2/conf.d/*.conf"
Include "/etc/apache2/conf.d/includes/account_suspensions.conf"
Include "/etc/apache2/conf.d/includes/errordocument.conf"
# Administrator locations for safely globally altering all virtualhost configurations
Include "/etc/apache2/conf.d/includes/pre_virtualhost_global.conf"
ProxyPass /___proxy_subdomain_ws_cpanel ws://127.0.0.1:2082 max=1 retry=0
ProxyPass /___proxy_subdomain_ws_whm ws://127.0.0.1:2086 max=1 retry=0
ProxyPass /___proxy_subdomain_ws_webmail ws://127.0.0.1:2095 max=1 retry=0