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
```
Some upstream repos still need fixes, but this gets us close enough that
style hints can be enabled by default.
In general, "canonical" spellings are preferred even if they violate
nep-1 - this applies in particular to spec-related stuff like
`genesis_validators_root` which appears throughout the codebase.
rocksdb was never actually used in nimbus-eth2 and existed only to satisfy nim-eth dependencies for test running - these have since moved to nimbus-eth1.
* bump nim-eth
`.era` files and Req/Resp protocols use framed formats - aligning the
database with these makes for less recompression work overall as gossip
is sent only once while req/resp repeats (potentially) - this also
allows efficient pruning-to-era where snappy-recompression is the major
cycle thief.
Changes in nim-eth relevant to nimbus-eth2:
- Style fixes according to --styleCheck:usages (#452)
- Add discoveryv5 session metrics (#454)
- Don’t use exceptions for enr get call (#453)
- Add DiscoveryConfig to tune routing table ip limits and bitPerHops
- More --styleCheck fixes for discoveryv5 and eth/common (#473)
The added options work in opt-in fashion. If they are not specified,
the server will respond to all requests as if the CORS specification
doesn't exist. This will result in errors in CORS-enabled clients.
Please note that future versions may support more than one allowed
origin. The option names will stay the same, but the user will be
able to repeat them on the command line (similar to other options
such as --web3-url).
To be documented in the guide in a separate PR.
* Fix a resource leak introduced in https://github.com/status-im/nimbus-eth2/pull/3279
* Don't restart the Eth1 syncing proggress from scratch in case of
monitor failures during Eth2 syncing.
* Switch to the primary operator as soon as it is back online.
* Log the web3 credentials in fewer places
Other changes:
The 'web3 test' command has been enhanced to obtain and print more
data regarding the selected provider.
* Store finalized block roots in database (3s startup)
When the chain has finalized a checkpoint, the history from that point
onwards becomes linear - this is exploited in `.era` files to allow
constant-time by-slot lookups.
In the database, we can do the same by storing finalized block roots in
a simple sparse table indexed by slot, bringing the two representations
closer to each other in terms of conceptual layout and performance.
Doing so has a number of interesting effects:
* mainnet startup time is improved 3-5x (3s on my laptop)
* the _first_ startup might take slightly longer as the new index is
being built - ~10s on the same laptop
* we no longer rely on the beacon block summaries to load the full dag -
this is a lot faster because we no longer have to look up each block by
parent root
* a collateral benefit is that we no longer need to load the full
summaries table into memory - we get the RSS benefits of #3164 without
the CPU hit.
Other random stuff:
* simplify forky block generics
* fix withManyWrites multiple evaluation
* fix validator key cache not being updated properly in chaindag
read-only mode
* drop pre-altair summaries from `kvstore`
* recreate missing summaries from altair+ blocks as well (in case
database has lost some to an involuntary restart)
* print database startup timings in chaindag load log
* avoid allocating superfluos state at startup
* use a recursive sql query to load the summaries of the unfinalized
blocks