Yes but at least in my experience as things fit in RAM, InnoDB is still the correct choice.
TokuDB is great once you run out of RAM-related solutions but given the price point RAM is at these days, we are talking 100GB+ tables which probably shouldn't be one a single machine anyway.
The machine isn't even that beefy, 128 GB of RAM, dual mid range Xeons, and prosumer SSDs in RAID 10. I would rather spend money in PCI-E SSDs, 300+ GB of RAM, and high end CPUs if it meant I didn't have to implement sharding at an application level.
You can comfortably handle multi-tera tables on single machines these days. Adding more machines isn't "scaling", its admitting "we can't scale in software so make it a hardware problem"
If your dataset fits in ram, and when it doesn't you have to buy more boxes with more ram rather than just buying more disk, then I think you are making a very uneconomical trade off.
> If your dataset fits in ram, and when it doesn't you have to buy more boxes with more ram rather than just buying more disk, then I think you are making a very uneconomical trade off.
It is all in what lower latency is worth to the bottom line and how well you scale horizontally.
(Src: have run each, and stuff like shard-query to parallelise queries and scale them out)