Add sysctl for server configuration

tools/sysctl.conf

@@ -0,0 +1,45 @@
+## Kernel Optimizations for few very high bandwidth connections.
+
+# Quickly with this:
+# curl -fsSL https://updates.safing.io/internal/sysctl.conf > /etc/sysctl.d/9999-spn-network-optimizing.conf
+# cat /etc/sysctl.d/9999-spn-network-optimizing.conf
+# sysctl -p /etc/sysctl.d/9999-spn-network-optimizing.conf
+
+# Provide adequate buffer memory.
+# net.ipv4.tcp_mem is in 4096-byte pages.
+net.core.rmem_max = 1073741824
+net.core.wmem_max = 1073741824
+net.core.rmem_default = 16777216
+net.core.wmem_default = 16777216
+net.ipv4.tcp_rmem = 4096 16777216 1073741824
+net.ipv4.tcp_wmem = 4096 16777216 1073741824
+net.ipv4.tcp_mem = 4194304 8388608 16777216
+net.ipv4.udp_rmem_min = 16777216
+net.ipv4.udp_wmem_min = 16777216
+
+# Enable TCP window scaling.
+net.ipv4.tcp_window_scaling = 1
+
+# Increase the length of the processor input queue
+net.core.netdev_max_backlog = 100000
+net.core.netdev_budget = 1000
+net.core.netdev_budget_usecs = 10000
+
+# Set better congestion control.
+net.ipv4.tcp_congestion_control = htcp
+
+# Turn off fancy stuff for more stability.
+net.ipv4.tcp_sack = 0
+net.ipv4.tcp_dsack = 0
+net.ipv4.tcp_fack = 0
+net.ipv4.tcp_timestamps = 0
+
+# Max reorders before slow start.
+net.ipv4.tcp_reordering = 3
+
+# Prefer low latency to higher throughput.
+# Disables IPv4 TCP prequeue processing.
+net.ipv4.tcp_low_latency = 1
+
+# Don't start slow.
+net.ipv4.tcp_slow_start_after_idle = 0