net.core.rmem_max = 16777216
net.core.wmem_max = 16777216
net.core.rmem_default = 16777216
net.core.wmem_default = 16777216
net.ipv4.tcp_rmem = 4096 87380 16777216
net.ipv4.tcp_wmem = 4096 87380 16777216
# This server might have 200 clients simultaneously, so:
# max(tcp_wmem) * 2 * 200 / 4096
net.ipv4.tcp_mem = 1638400 1638400 1638400

# Disable TCP SACK (TCP Selective Acknowledgement),
# DSACK (duplicate TCP SACK), and FACK (Forward Acknowledgement)
net.ipv4.tcp_sack = 0
net.ipv4.tcp_dsack = 0
net.ipv4.tcp_fack = 0

# Disable the gradual speed increase that's useful
# on variable-speed WANs but not for us
net.ipv4.tcp_slow_start_after_idle = 0