Space does not allow us to discuss this group of settings in detail. Consider them food for thought and online research.  Most mainstream Linux distributions come out of the box tuned to run on even modest hardware.  Systems like Ceph that do heavy network traffic can benefit considerably from tuning.

net.ipv4.tcp_timestamps=0
net.ipv4.tcp_sack=1
net.core.netdev_max_backlog=250000
net.ipv4.tcp_max_syn_backlog=100000
net.ipv4.tcp_max_tw_buckets=2000000
net.ipv4.tcp_tw_reuse=1
net.core.rmem_max=4194304
net.core.wmem_max=4194304
net.core.rmem_default=4194304
net.core.wmem_default=4194304
net.core.optmem_max=4194304
net.ipv4.tcp_rmem="4096 87380 4194304"
net.ipv4.tcp_wmem="4096 65536 4194304"
net.ipv4.tcp_low_latency=1
net.ipv4.tcp_adv_win_scale=1
net.ipv4.tcp_slow_start_after_idle=0
net.ipv4.tcp_no_metrics_save=1
net.ipv4.tcp_syncookies=0
net.core.somaxconn=5000
net.ipv4.tcp_ecn=0
net.ipv4.conf.all.send_redirects=0
net.ipv4.conf.all.accept_source_route=0
net.ipv4.icmp_echo_ignore_broadcasts=1
net.ipv4.tcp_no_metrics_save=1
net.ipv4.tcp_slow_start_after_idle=0
net.ipv4.tcp_fin_timeout=10