Your current Apache configuration shows several suboptimal settings for a resource-constrained server. The E6500 CPU (a 2009 dual-core processor) combined with 2GB RAM creates a challenging environment for handling 10K+ WordPress requests. Let's break down the critical issues:

# Current problematic settings:
MaxClients 80       # Way too high for 2GB RAM
StartServers 5      # Wastes memory for low-traffic periods
KeepAliveTimeout 2  # Too high for WordPress

For WordPress on limited hardware, prefork is still the most stable choice despite not being the most efficient. Here's my battle-tested configuration:

    StartServers         2
    MinSpareServers      2
    MaxSpareServers      5
    MaxClients           30
    MaxRequestsPerChild  500
    ServerLimit          30

Apache is only part of the equation. These PHP settings in your php.ini will help:

memory_limit = 128M        # Down from default 256M
max_execution_time = 30    # WordPress rarely needs more
opcache.enable=1           # Critical for PHP performance
opcache.memory_consumption=64
opcache.max_accelerated_files=4000

While KeepAlive improves performance for static sites, it's detrimental for WordPress. Each kept-alive connection consumes a precious Apache process. Modify these settings:

KeepAlive Off
# If you must keep it on:
KeepAlive On
KeepAliveTimeout 1
MaxKeepAliveRequests 50

Your W3 Total Cache setup needs these adjustments:

# In wp-config.php:
define('WP_CACHE', true);
define('W3TC_DYNAMIC_SECURITY', 'y0urS3cr3tC0d3');

# In .htaccess (replace existing rules):
<IfModule mod_rewrite.c>
    RewriteEngine On
    RewriteBase /
    RewriteCond %{REQUEST_METHOD} !=POST
    RewriteCond %{QUERY_STRING} =""
    RewriteCond %{HTTP_COOKIE} !(comment_author|wp-postpass|wordpress_logged_in|wptouch_switch_toggle) [NC]
    RewriteCond %{REQUEST_URI} !^(/wp-admin/|/xmlrpc.php|/wp-.*.php|/feed/|/index.php) [NC]
    RewriteCond %{HTTP:Accept-Encoding} gzip
    RewriteCond %{DOCUMENT_ROOT}/wp-content/cache/page_enhanced/%{HTTP_HOST}/%{REQUEST_URI}/_index.html.gz -f
    RewriteRule ^(.*)$ /wp-content/cache/page_enhanced/%{HTTP_HOST}/$1/_index.html.gz [L]
</IfModule>

Create this simple bash script to monitor and automatically handle overload situations:

#!/bin/bash
LOAD=$(cat /proc/loadavg | awk '{print $1}')
THRESHOLD=3.0 # Adjust based on your CPU cores

if (( $(echo "$LOAD > $THRESHOLD" | bc -l) )); then
    APACHE_MEM=$(ps -ylC apache2 | awk '{x += $8}END{print x/1024}')
    if (( $(echo "$APACHE_MEM > 1500" | bc -l) )); then
        service apache2 graceful
        echo "$(date) - Restarted Apache (Memory: $APACHE_MEM MB)" >> /var/log/apache_watchdog.log
    fi
fi

For extreme cases, replacing Apache with Nginx or LiteSpeed can yield 2-3x better performance on the same hardware:

# Sample Nginx WordPress config snippet
location / {
    try_files $uri $uri/ /index.php?$args;
}

location ~ \.php$ {
    fastcgi_pass unix:/run/php/php7.4-fpm.sock;
    include fastcgi_params;
    fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name;
}

When running WordPress with 10K+ daily pageviews on a 2GB RAM E6500 CPU server, the default Apache configuration becomes a critical limiting factor. The current setup shows symptoms of resource exhaustion - periodic unresponsiveness and the need for Apache restarts indicates we're hitting process/memory limits.

The provided config mixes prefork, worker and event MPM settings - this is problematic because only one MPM can be active at a time. On Ubuntu, Apache typically uses the prefork MPM for PHP processing. Key issues in the current setup:

# Problematic settings in current configuration
MaxClients 80        # Too high for 2GB RAM
MaxRequestsPerChild 1000  # May cause PHP memory leaks
StartServers 5       # Could be optimized for traffic patterns

For a 2GB RAM server with PHP/WordPress, these prefork settings balance performance and stability:

    StartServers            3
    MinSpareServers         3
    MaxSpareServers         6
    MaxClients             30
    MaxRequestsPerChild   500

Calculation method: Each Apache process typically consumes 30-50MB RAM with PHP. For 2GB RAM:
(2000MB - 500MB system/MySQL) / 40MB ≈ 37 processes max
We set MaxClients to 30 for safety margin.

Pair these Apache changes with PHP optimizations:

; php.ini adjustments
memory_limit = 96M          # Down from default 128M
max_execution_time = 60     # Reduced from 300
opcache.enable=1            # Enable OPcache
opcache.memory_consumption=128
opcache.interned_strings_buffer=8

For W3TC with APC, ensure these settings:

• Use Disk:Enhanced for page cache
• Enable Object Cache with APC
• Set browser cache headers aggressively

For more advanced setups, consider event MPM with PHP-FPM:

sudo apt install apache2-mpm-event php-fpm

Then configure:

    ServerLimit             16
    StartServers            3
    MinSpareThreads        25
    MaxSpareThreads        75
    ThreadLimit            64
    ThreadsPerChild        25
    MaxClients            400
    MaxRequestsPerChild  2000

After changes, monitor with:

watch -n 1 "echo -n 'Apache: '; ps -C apache2 --no-headers | wc -l; echo -n 'Memory free: '; free -m | awk '/Mem:/ {print \$4}'"

Adjust MaxClients based on real-world memory usage during peak traffic.