Why use websocket over http? A webSocket is a continuous connection between client and server. That continuous connection allows the following: Data can be sent from server to client at any time, without the client even requesting it. This is often called server-push and is very valuable for applications where the client needs to know … Read more
I’m the CTO of a small company that makes and sells FPGA-based HFT systems. Building our systems on-top of the Solarflare Application Onload Engine (AOE) we have been consistently delivering latency from an “interesting” market event on the wire (10Gb/S UDP market data feed from ICE or CME) to the first byte of the resultant … Read more
Which parts of the code should you warm up? Usually, you don’t have to do anything. However for a low latency application, you should warmup the critical path in your system. You should have unit tests, so I suggest you run those on start up to warmup up the code. Even once your code is … Read more
I thought this was a reasonable question and had researched it briefly a while back. I spent a little time searching for examples that you may be able to pick up some helpful tips from. Examples I like to begin with straight forward examples: light im sample code Node.js + Redis Pub/Sub + socket.io demo … Read more
TL;DR: You should not put BLIND trust into anything. First things first: it is important to verify the experimental data before jumping to the conclusions from them. Just claiming something is 3x faster/slower is odd, because you really need to follow up on the reason for the performance difference, not just trust the numbers. This … Read more
Numbers everyone should know 0.5 ns – CPU L1 dCACHE reference 1 ns – speed-of-light (a photon) travel a 1 ft (30.5cm) distance 5 ns – CPU L1 iCACHE Branch mispredict 7 ns – CPU L2 CACHE reference 71 ns – CPU cross-QPI/NUMA best case on XEON E5-46* 100 ns – MUTEX lock/unlock 100 ns … Read more