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pezkuwi-subxt/polkadot/node/subsystem-bench/src/lib/configuration.rs
T
Aaro Altonen 80616f6d03 Integrate litep2p into Polkadot SDK (#2944)
[litep2p](https://github.com/altonen/litep2p) is a libp2p-compatible P2P
networking library. It supports all of the features of `rust-libp2p`
that are currently being utilized by Polkadot SDK.

Compared to `rust-libp2p`, `litep2p` has a quite different architecture
which is why the new `litep2p` network backend is only able to use a
little of the existing code in `sc-network`. The design has been mainly
influenced by how we'd wish to structure our networking-related code in
Polkadot SDK: independent higher-levels protocols directly communicating
with the network over links that support bidirectional backpressure. A
good example would be `NotificationHandle`/`RequestResponseHandle`
abstractions which allow, e.g., `SyncingEngine` to directly communicate
with peers to announce/request blocks.

I've tried running `polkadot --network-backend litep2p` with a few
different peer configurations and there is a noticeable reduction in
networking CPU usage. For high load (`--out-peers 200`), networking CPU
usage goes down from ~110% to ~30% (80 pp) and for normal load
(`--out-peers 40`), the usage goes down from ~55% to ~18% (37 pp).

These should not be taken as final numbers because:

a) there are still some low-hanging optimization fruits, such as
enabling [receive window
auto-tuning](https://github.com/libp2p/rust-yamux/pull/176), integrating
`Peerset` more closely with `litep2p` or improving memory usage of the
WebSocket transport
b) fixing bugs/instabilities that incorrectly cause `litep2p` to do less
work will increase the networking CPU usage
c) verification in a more diverse set of tests/conditions is needed

Nevertheless, these numbers should give an early estimate for CPU usage
of the new networking backend.

This PR consists of three separate changes:
* introduce a generic `PeerId` (wrapper around `Multihash`) so that we
don't have use `NetworkService::PeerId` in every part of the code that
uses a `PeerId`
* introduce `NetworkBackend` trait, implement it for the libp2p network
stack and make Polkadot SDK generic over `NetworkBackend`
  * implement `NetworkBackend` for litep2p

The new library should be considered experimental which is why
`rust-libp2p` will remain as the default option for the time being. This
PR currently depends on the master branch of `litep2p` but I'll cut a
new release for the library once all review comments have been
addresses.

---------

Signed-off-by: Alexandru Vasile <alexandru.vasile@parity.io>
Co-authored-by: Dmitry Markin <dmitry@markin.tech>
Co-authored-by: Alexandru Vasile <60601340+lexnv@users.noreply.github.com>
Co-authored-by: Alexandru Vasile <alexandru.vasile@parity.io>
2024-04-08 16:44:13 +00:00

262 lines
7.7 KiB
Rust

// Copyright (C) Parity Technologies (UK) Ltd.
// This file is part of Polkadot.
// Polkadot is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// Polkadot is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with Polkadot. If not, see <http://www.gnu.org/licenses/>.
//! Test configuration definition and helpers.
use crate::keyring::Keyring;
use itertools::Itertools;
use polkadot_primitives::{AssignmentId, AuthorityDiscoveryId, ValidatorId};
use rand::thread_rng;
use rand_distr::{Distribution, Normal, Uniform};
use sc_network_types::PeerId;
use serde::{Deserialize, Serialize};
use sp_consensus_babe::AuthorityId;
use std::collections::HashMap;
/// Peer networking latency configuration.
#[derive(Clone, Debug, Default, Serialize, Deserialize)]
pub struct PeerLatency {
/// The mean latency(milliseconds) of the peers.
pub mean_latency_ms: usize,
/// The standard deviation
pub std_dev: f64,
}
// Based on Kusama `max_validators`
fn default_n_validators() -> usize {
300
}
// Based on Kusama cores
fn default_n_cores() -> usize {
60
}
// Default PoV size in KiB.
fn default_pov_size() -> usize {
5 * 1024
}
// Default bandwidth in bytes, based stats from Kusama validators
fn default_bandwidth() -> usize {
42 * 1024 * 1024
}
// Default peer latency
fn default_peer_latency() -> Option<PeerLatency> {
Some(PeerLatency { mean_latency_ms: 30, std_dev: 2.0 })
}
// Default connectivity percentage
fn default_connectivity() -> usize {
90
}
// Default backing group size
fn default_backing_group_size() -> usize {
5
}
// Default needed approvals
fn default_needed_approvals() -> usize {
30
}
fn default_zeroth_delay_tranche_width() -> usize {
0
}
fn default_relay_vrf_modulo_samples() -> usize {
6
}
fn default_n_delay_tranches() -> usize {
89
}
fn default_no_show_slots() -> usize {
3
}
/// The test input parameters
#[derive(Clone, Debug, Serialize, Deserialize)]
pub struct TestConfiguration {
/// Number of validators
#[serde(default = "default_n_validators")]
pub n_validators: usize,
/// Number of cores
#[serde(default = "default_n_cores")]
pub n_cores: usize,
/// The number of needed votes to approve a candidate.
#[serde(default = "default_needed_approvals")]
pub needed_approvals: usize,
#[serde(default = "default_zeroth_delay_tranche_width")]
pub zeroth_delay_tranche_width: usize,
#[serde(default = "default_relay_vrf_modulo_samples")]
pub relay_vrf_modulo_samples: usize,
#[serde(default = "default_n_delay_tranches")]
pub n_delay_tranches: usize,
#[serde(default = "default_no_show_slots")]
pub no_show_slots: usize,
/// Maximum backing group size
#[serde(default = "default_backing_group_size")]
pub max_validators_per_core: usize,
/// The min PoV size
#[serde(default = "default_pov_size")]
pub min_pov_size: usize,
/// The max PoV size,
#[serde(default = "default_pov_size")]
pub max_pov_size: usize,
/// Randomly sampled pov_sizes
#[serde(skip)]
pub pov_sizes: Vec<usize>,
/// The amount of bandwidth remote validators have.
#[serde(default = "default_bandwidth")]
pub peer_bandwidth: usize,
/// The amount of bandwidth our node has.
#[serde(default = "default_bandwidth")]
pub bandwidth: usize,
/// Optional peer emulation latency (round trip time) wrt node under test
#[serde(default = "default_peer_latency")]
pub latency: Option<PeerLatency>,
/// Connectivity ratio, the percentage of peers we are connected to, but as part of the
/// topology.
#[serde(default = "default_connectivity")]
pub connectivity: usize,
/// Number of blocks to run the test for
pub num_blocks: usize,
}
impl Default for TestConfiguration {
fn default() -> Self {
Self {
n_validators: default_n_validators(),
n_cores: default_n_cores(),
needed_approvals: default_needed_approvals(),
zeroth_delay_tranche_width: default_zeroth_delay_tranche_width(),
relay_vrf_modulo_samples: default_relay_vrf_modulo_samples(),
n_delay_tranches: default_n_delay_tranches(),
no_show_slots: default_no_show_slots(),
max_validators_per_core: default_backing_group_size(),
min_pov_size: default_pov_size(),
max_pov_size: default_pov_size(),
pov_sizes: Default::default(),
peer_bandwidth: default_bandwidth(),
bandwidth: default_bandwidth(),
latency: default_peer_latency(),
connectivity: default_connectivity(),
num_blocks: Default::default(),
}
}
}
impl TestConfiguration {
pub fn generate_pov_sizes(&mut self) {
self.pov_sizes = generate_pov_sizes(self.n_cores, self.min_pov_size, self.max_pov_size);
}
pub fn pov_sizes(&self) -> &[usize] {
&self.pov_sizes
}
/// Return the number of peers connected to our node.
pub fn connected_count(&self) -> usize {
((self.n_validators - 1) as f64 / (100.0 / self.connectivity as f64)) as usize
}
/// Generates the authority keys we need for the network emulation.
pub fn generate_authorities(&self) -> TestAuthorities {
let keyring = Keyring::default();
let key_seeds = (0..self.n_validators)
.map(|peer_index| format!("//Node{}", peer_index))
.collect_vec();
let keys = key_seeds
.iter()
.map(|seed| keyring.sr25519_new(seed.as_str()))
.collect::<Vec<_>>();
// Generate keys and peers ids in each of the format needed by the tests.
let validator_public: Vec<ValidatorId> =
keys.iter().map(|key| (*key).into()).collect::<Vec<_>>();
let validator_authority_id: Vec<AuthorityDiscoveryId> =
keys.iter().map(|key| (*key).into()).collect::<Vec<_>>();
let validator_babe_id: Vec<AuthorityId> =
keys.iter().map(|key| (*key).into()).collect::<Vec<_>>();
let validator_assignment_id: Vec<AssignmentId> =
keys.iter().map(|key| (*key).into()).collect::<Vec<_>>();
let peer_ids: Vec<PeerId> = keys.iter().map(|_| PeerId::random()).collect::<Vec<_>>();
let peer_id_to_authority = peer_ids
.iter()
.zip(validator_authority_id.iter())
.map(|(peer_id, authority_id)| (*peer_id, authority_id.clone()))
.collect();
TestAuthorities {
keyring,
validator_public,
validator_authority_id,
peer_ids,
validator_babe_id,
validator_assignment_id,
key_seeds,
peer_id_to_authority,
}
}
}
fn random_uniform_sample<T: Into<usize> + From<usize>>(min_value: T, max_value: T) -> T {
Uniform::from(min_value.into()..=max_value.into())
.sample(&mut thread_rng())
.into()
}
fn random_pov_size(min_pov_size: usize, max_pov_size: usize) -> usize {
random_uniform_sample(min_pov_size, max_pov_size)
}
fn generate_pov_sizes(count: usize, min_kib: usize, max_kib: usize) -> Vec<usize> {
(0..count).map(|_| random_pov_size(min_kib * 1024, max_kib * 1024)).collect()
}
/// Helper struct for authority related state.
#[derive(Clone)]
pub struct TestAuthorities {
pub keyring: Keyring,
pub validator_public: Vec<ValidatorId>,
pub validator_authority_id: Vec<AuthorityDiscoveryId>,
pub validator_babe_id: Vec<AuthorityId>,
pub validator_assignment_id: Vec<AssignmentId>,
pub key_seeds: Vec<String>,
pub peer_ids: Vec<PeerId>,
pub peer_id_to_authority: HashMap<PeerId, AuthorityDiscoveryId>,
}
/// Sample latency (in milliseconds) from a normal distribution with parameters
/// specified in `maybe_peer_latency`.
pub fn random_latency(maybe_peer_latency: Option<&PeerLatency>) -> usize {
maybe_peer_latency
.map(|latency_config| {
Normal::new(latency_config.mean_latency_ms as f64, latency_config.std_dev)
.expect("normal distribution parameters are good")
.sample(&mut thread_rng())
})
.unwrap_or(0.0) as usize
}