Tune PHP-FPM Performance on Ubuntu 24.04

Estimate pm.max_children

ps -ylC php-fpm --no-headers | awk '{sum+=$8} END {print sum/NR/1024 " MB avg"}'
# Divide available RAM (minus OS+DB) by average size

Recommended dynamic settings

pm = dynamic
pm.max_children      = 50
pm.start_servers     =...

Tune PostgreSQL Performance on Ubuntu 24.04

postgresql.conf

# Memory
shared_buffers          = 2GB       # 25% of RAM
effective_cache_size    = 6GB       # 50-75% of RAM
work_mem                = 64MB      # per-sort/hash
maintenance_work_mem    = 512MB

# Checkpoints
checkpoint_completion_targe...

Tune Varnish Cache on Ubuntu 24.04

Systemd override (/etc/systemd/system/varnish.service.d/override.conf)

[Service]
ExecStart=
ExecStart=/usr/sbin/varnishd \
    -a :80 -T localhost:6082 \
    -f /etc/varnish/default.vcl \
    -s malloc,2G \
    -p thread_pools=2 \
    -p thread_pool_min=200 \...

Varnish VCL Configuration on Ubuntu 24.04

Full example with load balancing and grace

vcl 4.1;
import directors;

backend web1 {
    .host = "192.168.1.10"; .port = "8080";
    .probe = { .url = "/health"; .timeout = 5s; .interval = 10s; .window = 5; .threshold = 3; }
}
backend web2 {
    .host =...