I was doing some digging into Solana, mostly because Sam of FTX is a backer and a big fan of it, and since it seems to me that FTX may be in the running for a future IPO, I wanted to know more about why they use Solana and feature it so prominently in their exchange and their marketing. There are some things [I don’t understand about their terminology](https://genesisblockhk.com/what-is-solana/).
The biggest question is: Doesn’t Solana (on face value) solve all of the things that Ethereum was trying to do with sharding?
They have something called Gulf Stream. Their marketing documentation says “This allows the validators to **execute the transactions ahead of time**, reducing confirmation time, faster leader switching, and reduced memory pressure on validators from unconfirmed transaction pools.”
What does executing transactions ahead of time mean? I mean, if the proof algorithm is based on Proof of History, which is some kind of chronology of timestamps and a clock, what does pushing it ahead of time mean? How can something be out of sync chronologically and still be in sync in proof of history? I am really confused about that.
“Sealevel is a hyper parallelized transaction processing engine that is used to scale horizontally across GPUs and SSDs. With this system in place, it allows Solana to obtain a more efficient runtime and also allow transactions to run concurrently on the same state blockchains. ”
Does the above mean that data from a single transaction, or group of transactions is split at the GPU and SSD level on the same machines? Sorry if I don’t understand this, but it seems they are just defragging the data and mixing it in different data centres / data clocks.
If data is split by time and machine parts within a single machine, and then also across a network, what brings it all back together? I assume that the machines working on the data transaction are also stamping it with a time limit and within a specific run time it has to come back to be parsed and then sent in packets back to some kind of history check?