Multithreading is hard

There are many ways to kill performance in a multithreaded program. My favorite one is false sharing, because you can get 10x performance just by moving some bytes around. So let's look into it. 00:00 - When multiple threads is not even faster 04:23 - CPU L1 cache primer 09:40 - Getting ALL the performance 15:35 - Looking at disassembler 20:29 - How to find cache line address 22:38 - false sharing in disassembly 25:00 - closing words