Jacek Sieka d0dbc4a8f9
Snappy revamp (#3564)
This PR makes the necessary adjustments to deal with the revamped snappy
API.

In practical terms for nimbus-eth2, there are performance increases to
gossip processing, database reading and writing as well as era file
processing. Exporting `.era` files for example, a snappy-heavy
operation, almost halves in total processing time:

Pre:

```
     Average,       StdDev,          Min,          Max,      Samples,         Test
      39.088,        8.735,       23.619,       53.301,           50, tState
     237.079,       46.692,      165.620,      355.481,           49, tBlocks
```

Post:

```
All time are ms
     Average,       StdDev,          Min,          Max,      Samples,         Test
      25.350,        5.303,       15.351,       41.856,           50, tState
     141.238,       24.164,       99.990,      199.329,           49, tBlocks
```
2022-04-15 09:44:06 +02:00
..
2022-04-15 09:44:06 +02:00
2021-03-26 07:52:01 +01:00
2021-03-05 14:12:00 +01:00

Networking

This folders hold a collection of modules to:

  • configure the Eth2 P2P network
  • discover, connect, and maintain quality Eth2 peers

Data received is handed other to the ../gossip_processing modules for validation.

Security concerns

  • Collusion: part of the peer selection must be kept random. This avoids peers bringing all their friends and colluding against a beacon node.
  • Denial-of-service: The beacon node must provide ways to handle burst of data that may come:
    • from malicious nodes trying to DOS us
    • from long periods of non-finality, creating lots of forks, attestations, forks