The Unreasonable Effectiveness of Tuning
The Unreasonable Effectiveness of Tuning
Counter-intuitively, the effects of tuning (tweaks to a system in response to real workloads) often dominate the effects of fundamentally better technology. Well-tuned, bad systems usually outperform less mature, better systems.
In this talk, Facebook’s Keith Adams, co-founder of HHVM, the runtime which powers the largest website in the world, will cover:
One of the examples covered will be Facebook’s HipHop Virtual Machine, which was 7x slower than its performance target at the start. Today, it is 2x faster than that original goal. Yet the block-diagram level design of the system is unchanged. There have been no research breakthroughs, conceptual insights, or heroic ground-up rewrites. The 14x difference came instead from tuning: HHVM now does thousands of small things slightly better.