vm.swappiness = 20 (10)
net.core.somaxconn = 256 # max 512 before nginx backlog needs changing
net.core.netdev_max_backlog = 
net.core.rmem_default = 212992
net.core.rmem_max = 212992 # 16777216
net.core.wmem_default = 212992
net.core.wmem_max = 212992 # 16777216
net.ipv4.ip_local_port_range = 1024 65535
# Enables fast recycling of TIME_WAIT sockets.
# (Use with caution according to the kernel documentation!)
net.ipv4.tcp_tw_recycle = 1
# Allow reuse of sockets in TIME_WAIT state for new connections
# only when it is safe from the network stack’s perspective.
net.ipv4.tcp_tw_reuse = 1
# Increase the number of outstanding syn requests allowed.
# c.f. The use of syncookies.
net.ipv4.tcp_max_syn_backlog = 4096
net.ipv4.tcp_syncookies = 1
fs.file-max = 98236
# Forking servers, like PostgreSQL or Apache, scale to much
# higher levels of concurrent connections if this is made larger,
# by at least an order of magnitude:
kernel.sched_migration_cost_ns = 5000000
# PostgreSQL specific
kernel.sched_autogroup_enabled = 0

# generic noatime for system mounts