Updated Performance (markdown)

Performance.md

@@ -54,4 +54,21 @@ To be bold I created 2500 datasets, but that also was no problem. So it seems it
 
 If you need more performance let me know.
 
+## TCP tuning
+
+By default, the linux kernel uses `cubic` as the TCP Congestion Control protocol. This is extremely good for _almost_ all situations, except for moving huge amounts of data over the public internet where you can have brief bursts of congestion (and therefore packet loss).
+
+Changing this to `scaleable` makes TCP sessions recover much faster from packet loss, and return to the full speed available without the extended recovery of the normal `cubic` protocol.
+
+If you're sending data over the internet, this setting might help:
+
+/etc/sysctl.d/60-send-bulk-tcp.conf:
+```
+# Recovers rapidly from congestion
+net.ipv4.tcp_congestion_control = scalable
+```
+
+More info: https://en.wikipedia.org/wiki/Scalable_TCP
+
+(thanks @xrobau)