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  1. Mar 01, 2024
    • Andrei Eres's avatar
      subsystem-bench: add regression tests for availability read and write (#3311) · f0e589d7
      Andrei Eres authored 
      ### What's been done
- `subsystem-bench` has been split into two parts: a cli benchmark
runner and a library.
- The cli runner is quite simple. It just allows us to run `.yaml` based
test sequences. Now it should only be used to run benchmarks during
development.
- The library is used in the cli runner and in regression tests. Some
code is changed to make the library independent of the runner.
- Added first regression tests for availability read and write that
replicate existing test sequences.

### How we run regression tests
- Regression tests are simply rust integration tests without the
harnesses.
- They should only be compiled under the `subsystem-benchmarks` feature
to prevent them from running with other tests.
- This doesn't work when running tests with `nextest` in CI, so
additional filters have been added to the `nextest` runs.
- Each benchmark run takes a different time in the beginning, so we
"warm up" the tests until their CPU usage differs by only 1%.
- After the warm-up, we run the benchmarks a few more times and compare
the average with the exception using a precision.

### What is still wrong?
- I haven't managed to set up approval voting tests. The spread of their
results is too large and can't be narrowed down in a reasonable amount
of time in the warm-up phase.
- The tests start an unconfigurable prometheus endpoint inside, which
causes errors because they use the same 9999 port. I disable it with a
flag, but I think it's better to extract the endpoint launching outside
the test, as we already do with `valgrind` and `pyroscope`. But we still
use `prometheus` inside the tests.

### Future work
* https://github.com/paritytech/polkadot-sdk/issues/3528
* https://github.com/paritytech/polkadot-sdk/issues/3529
* https://github.com/paritytech/polkadot-sdk/issues/3530
* https://github.com/paritytech/polkadot-sdk/issues/3531



---------

Co-authored-by: default avatarAlexander Samusev <[email protected]>
      f0e589d7
    • Egor_P's avatar
      [Backport] Node version and spec_version bumps and ordering of the prdoc files from 1.8.0 (#3508) · 59b26614
      Egor_P authored 
      This PR backports Node version and `spec_version` bumps to `1.8.0` from
the latest release and orders prdoc files related to it.
      59b26614
  3. Feb 29, 2024
  5. Feb 28, 2024
    • Oliver Tale-Yazdi's avatar
      Multi-Block-Migrations, `poll` hook and new System callbacks (#1781) · eefd5fe4
      Oliver Tale-Yazdi authored 
      This MR is the merge of
https://github.com/paritytech/substrate/pull/14414 and
https://github.com/paritytech/substrate/pull/14275. It implements
[RFC#13](https://github.com/polkadot-fellows/RFCs/pull/13), closes
https://github.com/paritytech/polkadot-sdk/issues/198.

----- 

This Merge request introduces three major topicals:

1. Multi-Block-Migrations
1. New pallet `poll` hook for periodic service work
1. Replacement hooks for `on_initialize` and `on_finalize` in cases
where `poll` cannot be used

and some more general changes to FRAME.  
The changes for each topical span over multiple crates. They are listed
in topical order below.

# 1.) Multi-Block-Migrations

Multi-Block-Migrations are facilitated by creating `pallet_migrations`
and configuring `System::Config::MultiBlockMigrator` to point to it.
Executive picks this up and triggers one step of the migrations pallet
per block.
The chain is in lockdown mode for as long as an MBM is ongoing.
Executive does this by polling `MultiBlockMigrator::ongoing` and not
allowing any transaction in a block, if true.

A MBM is defined through trait `SteppedMigration`. A condensed version
looks like this:
```rust
/// A migration that can proceed in multiple steps.
pub trait SteppedMigration {
	type Cursor: FullCodec + MaxEncodedLen;
	type Identifier: FullCodec + MaxEncodedLen;

	fn id() -> Self::Identifier;

	fn max_steps() -> Option<u32>;

	fn step(
		cursor: Option<Self::Cursor>,
		meter: &mut WeightMeter,
	) -> Result<Option<Self::Cursor>, SteppedMigrationError>;
}
```

`pallet_migrations` can be configured with an aggregated tuple of these
migrations. It then starts to migrate them one-by-one on the next
runtime upgrade.
Two things are important here:
- 1. Doing another runtime upgrade while MBMs are ongoing is not a good
idea and can lead to messed up state.
- 2. **Pallet Migrations MUST BE CONFIGURED IN `System::Config`,
otherwise it is not used.**

The pallet supports an `UpgradeStatusHandler` that can be used to notify
external logic of upgrade start/finish (for example to pause XCM
dispatch).

Error recovery is very limited in the case that a migration errors or
times out (exceeds its `max_steps`). Currently the runtime dev can
decide in `FailedMigrationHandler::failed` how to handle this. One
follow-up would be to pair this with the `SafeMode` pallet and enact
safe mode when an upgrade fails, to allow governance to rescue the
chain. This is currently not possible, since governance is not
`Mandatory`.

## Runtime API

- `Core`: `initialize_block` now returns `ExtrinsicInclusionMode` to
inform the Block Author whether they can push transactions.

### Integration

Add it to your runtime implementation of `Core` and `BlockBuilder`:
```patch
diff --git a/runtime/src/lib.rs b/runtime/src/lib.rs
@@ impl_runtime_apis! {
	impl sp_block_builder::Core<Block> for Runtime {
-		fn initialize_block(header: &<Block as BlockT>::Header) {
+		fn initialize_block(header: &<Block as BlockT>::Header) -> RuntimeExecutiveMode {
			Executive::initialize_block(header)
		}

		...
	}
```

# 2.) `poll` hook

A new pallet hook is introduced: `poll`. `Poll` is intended to replace
mostly all usage of `on_initialize`.
The reason for this is that any code that can be called from
`on_initialize` cannot be migrated through an MBM. Currently there is no
way to statically check this; the implication is to use `on_initialize`
as rarely as possible.
Failing to do so can result in broken storage invariants.

The implementation of the poll hook depends on the `Runtime API` changes
that are explained above.

# 3.) Hard-Deadline callbacks

Three new callbacks are introduced and configured on `System::Config`:
`PreInherents`, `PostInherents` and `PostTransactions`.
These hooks are meant as replacement for `on_initialize` and
`on_finalize` in cases where the code that runs cannot be moved to
`poll`.
The reason for this is to make the usage of HD-code (hard deadline) more
explicit - again to prevent broken invariants by MBMs.

# 4.) FRAME (general changes)

## `frame_system` pallet

A new memorize storage item `InherentsApplied` is added. It is used by
executive to track whether inherents have already been applied.
Executive and can then execute the MBMs directly between inherents and
transactions.

The `Config` gets five new items:
- `SingleBlockMigrations` this is the new way of configuring migrations
that run in a single block. Previously they were defined as last generic
argument of `Executive`. This shift is brings all central configuration
about migrations closer into view of the developer (migrations that are
configured in `Executive` will still work for now but is deprecated).
- `MultiBlockMigrator` this can be configured to an engine that drives
MBMs. One example would be the `pallet_migrations`. Note that this is
only the engine; the exact MBMs are injected into the engine.
- `PreInherents` a callback that executes after `on_initialize` but
before inherents.
- `PostInherents` a callback that executes after all inherents ran
(including MBMs and `poll`).
- `PostTransactions` in symmetry to `PreInherents`, this one is called
before `on_finalize` but after all transactions.

A sane default is to set all of these to `()`. Example diff suitable for
any chain:
```patch
@@ impl frame_system::Config for Test {
 	type MaxConsumers = ConstU32<16>;
+	type SingleBlockMigrations = ();
+	type MultiBlockMigrator = ();
+	type PreInherents = ();
+	type PostInherents = ();
+	type PostTransactions = ();
 }
```

An overview of how the block execution now looks like is here. The same
graph is also in the rust doc.

<details><summary>Block Execution Flow</summary>
<p>

![Screenshot 2023-12-04 at 19 11
29](https://github.com/paritytech/polkadot-sdk/assets/10380170/e88a80c4-ef11-4faa-8df5-8b33a724c054)

</p>
</details> 

## Inherent Order

Moved to https://github.com/paritytech/polkadot-sdk/pull/2154



---------------


## TODO

- [ ] Check that `try-runtime` still works
- [ ] Ensure backwards compatibility with old Runtime APIs
- [x] Consume weight correctly
- [x] Cleanup

---------

Signed-off-by: default avatarOliver Tale-Yazdi <[email protected]>
Co-authored-by: default avatarLiam Aharon <[email protected]>
Co-authored-by: default avatarJuan Girini <[email protected]>
Co-authored-by: command-bot <>
Co-authored-by: default avatarFrancisco Aguirre <[email protected]>
Co-authored-by: default avatarGavin Wood <[email protected]>
Co-authored-by: default avatarBastian Köcher <[email protected]>
      eefd5fe4
    • maksimryndin's avatar
      PVF: re-preparing artifact on failed runtime construction (#3187) · 42613667
      maksimryndin authored 
      resolve https://github.com/paritytech/polkadot-sdk/issues/3139

- [x] use a distinguishable error for `execute_artifact`
- [x] remove artifact in case of a `RuntimeConstruction` error during
the execution
- [x] augment the `validate_candidate_with_retry` of `ValidationBackend`
with the case of retriable `RuntimeConstruction` error during the
execution
- [x] update the book
(https://paritytech.github.io/polkadot-sdk/book/node/utility/pvf-host-and-workers.html#retrying-execution-requests

)
- [x] add a test
- [x] run zombienet tests

---------

Co-authored-by: default avatars0me0ne-unkn0wn <[email protected]>
      42613667
    • Liam Aharon's avatar
      Runtime Upgrade ref docs and Single Block Migration example pallet (#1554) · 12ce4f7d
      Liam Aharon authored 
      Closes https://github.com/paritytech/polkadot-sdk-docs/issues/55

- Changes 'current storage version' terminology to less ambiguous
'in-code storage version' (suggestion by @ggwpez)
- Adds a new example pallet `pallet-example-single-block-migrations`
- Adds a new reference doc to replace
https://docs.substrate.io/maintain/runtime-upgrades/ (temporarily living
in the pallet while we wait for developer hub PR to merge)
- Adds documentation for the `storage_alias` macro
- Improves `trait Hooks` docs 
- Improves `trait GetStorageVersion` docs
- Update the suggested patterns for using `VersionedMigration`, so that
version unchecked migrations are never exported
- Prevents accidental usage of version unchecked migrations in runtimes

https://github.com/paritytech/substrate/pull/14421#discussion_r1255467895
- Unversioned migration code is kept inside `mod version_unchecked`,
versioned code is kept in `pub mod versioned`
- It is necessary to use modules to limit visibility because the inner
migration must be `pub`. See
https://github.com/rust-lang/rust/issues/30905 and

https://internals.rust-lang.org/t/lang-team-minutes-private-in-public-rules/4504/40
for more.

### todo

- [x] move to reference docs to proper place within sdk-docs (now that
https://github.com/paritytech/polkadot-sdk/pull/2102

 is merged)
- [x] prdoc

---------

Co-authored-by: default avatarKian Paimani <[email protected]>
Co-authored-by: default avatarJuan <[email protected]>
Co-authored-by: default avatarOliver Tale-Yazdi <[email protected]>
Co-authored-by: command-bot <>
Co-authored-by: default avatargupnik <[email protected]>
      12ce4f7d
    • maksimryndin's avatar
      Collator overseer builder unification (#3335) · 7ec0b874
      maksimryndin authored 
      resolve https://github.com/paritytech/polkadot-sdk/issues/3116

a follow-up on
https://github.com/paritytech/polkadot-sdk/pull/3061#pullrequestreview-1847530265

:

- [x] reuse collator overseer builder for polkadot-node and collator
- [x] run zombienet test (0001-parachains-smoke-test.toml)
- [x] make wasm build errors more user-friendly for an easier problem
detection when using different toolchains in Rust

---------

Co-authored-by: default avatarordian <[email protected]>
Co-authored-by: default avatars0me0ne-unkn0wn <[email protected]>
      7ec0b874
  7. Feb 27, 2024
    • Petr Mensik's avatar
      Add Polkadotters bootnoders per IBP application (#3423) · 0cc9b900
      Petr Mensik authored 
      Hey everyone,

this PR will replace existing Polkadotters bootnodes for Polkadot,
Kusama and Westend and add Paseo bootnode to the relay chain suite. At
the same time, it will add new bootnodes for all the system parachains,
including People on Westend. This PR is a part of our membership in the
IBP, meaning that all the bootnodes are hosted on our hardware housed in
the data center in Christchurch, New Zealand.
All the bootnodes were tested with an empty chain spec file with the
following command yielding 1 peer.

The test commands used are as follows:
```
./polkadot --base-path /tmp/node --reserved-only --chain paseo --reserved-nodes "/dns/paseo.bootnodes.polkadotters.com/tcp/30540/wss/p2p/12D3KooWPbbFy4TefEGTRF5eTYhq8LEzc4VAHdNUVCbY4nAnhqPP"
./polkadot --base-path /tmp/node --reserved-only --chain westend --reserved-nodes "/dns/westend.bootnodes.polkadotters.com/tcp/30310/wss/p2p/12D3KooWHPHb64jXMtSRJDrYFATWeLnvChL8NtWVttY67DCH1eC5"
./polkadot --base-path /tmp/node --reserved-only --chain kusama --reserved-nodes "/dns/kusama.bootnodes.polkadotters.com/tcp/30313/wss/p2p/12D3KooWHB5rTeNkQdXNJ9ynvGz8Lpnmsctt7Tvp7mrYv6bcwbPG"
./polkadot --base-path /tmp/node --no-hardware-benchmarks --reserved-only --chain polkadot --reserved-nodes "/dns/polkadot.bootnodes.polkadotters.com/tcp/30316/wss/p2p/12D3KooWPAVUgBaBk6n8SztLrMk8ESByncbAfRKUdxY1nygb9zG3"
./polkadot-parachain --base-path /tmp/node --reserved-only --chain asset-hub-kusama --reserved-nodes "/dns/asset-hub-kusama.bootnodes.polkadotters.com/tcp/30513/wss/p2p/12D3KooWDpk7wVH7RgjErEvbvAZ2kY5VeaAwRJP5ojmn1e8b8UbU"
./polkadot-parachain --base-path /tmp/node --reserved-only --chain asset-hub-polkadot --reserved-nodes "/dns/asset-hub-polkadot.bootnodes.polkadotters.com/tcp/30510/wss/p2p/12D3KooWKbfY9a9oywxMJKiALmt7yhrdQkjXMtvxhhDDN23vG93R"
./polkadot-parachain --base-path /tmp/node --reserved-only --chain asset-hub-westend --reserved-nodes "/dns/asset-hub-westend.bootnodes.polkadotters.com/tcp/30516/wss/p2p/12D3KooWNFYysCqmojxqjjaTfD2VkWBNngfyUKWjcR4WFixfHNTk"
./polkadot-parachain --base-path /tmp/node --reserved-only --chain bridge-hub-kusama --reserved-nodes "/dns/bridge-hub-kusama.bootnodes.polkadotters.com/tcp/30522/wss/p2p/12D3KooWH3pucezRRS5esoYyzZsUkKWcPSByQxEvmM819QL1HPLV"
./polkadot-parachain --base-path /tmp/node --reserved-only --chain bridge-hub-kusama --reserved-nodes "/dns/bridge-hub-kusama.bootnodes.polkadotters.com/tcp/30522/wss/p2p/12D3KooWH3pucezRRS5esoYyzZsUkKWcPSByQxEvmM819QL1HPLV"
./polkadot-parachain --base-path /tmp/node --reserved-only --chain bridge-hub-westend --reserved-nodes "/dns/bridge-hub-westend.bootnodes.polkadotters.com/tcp/30525/wss/p2p/12D3KooWPkwgJofp4GeeRwNgXqkp2aFwdLkCWv3qodpBJLwK43Jj"
./polkadot-parachain --base-path /tmp/node --reserved-only --chain collectives-polkadot --reserved-nodes "/dns/collectives-polkadot.bootnodes.polkadotters.com/tcp/30528/wss/p2p/12D3KooWNohUjvJtGKUa8Vhy8C1ZBB5N8JATB6e7rdLVCioeb3ff"
./polkadot-parachain --base-path /tmp/node --reserved-only --chain collectives-westend --reserved-nodes "/dns/collectives-westend.bootnodes.polkadotters.com/tcp/30531/wss/p2p/12D3KooWAFkXNSBfyPduZVgfS7pj5NuVpbU8Ee5gHeF8wvos7Yqn"
./polkadot-parachain --base-path /tmp/node --reserved-only --chain people-westend --reserved-nodes "/dns/identity-westend.bootnodes.polkadotters.com/tcp/30534/wss/p2p/12D3KooWKr9San6KTM7REJ95cBaDoiciGcWnW8TTftEJgxGF5Ehb"
```

Best regards,

Petr, Polkadotters
      0cc9b900
  9. Feb 26, 2024
  11. Feb 23, 2024
  13. Feb 22, 2024
  15. Feb 20, 2024
    • Niklas Adolfsson's avatar
      rpc server: make possible to disable/enable batch requests (#3364) · fee810a5
      Niklas Adolfsson authored 
      The rationale behind this, is that it may be useful for some users
actually disable RPC batch requests or limit them by length instead of
the total size bytes of the batch.

This PR adds two new CLI options:

```
--rpc-disable-batch-requests - disable batch requests on the server
--rpc-max-batch-request-len <LEN> - limit batches to LEN on the server.
```
      fee810a5
    • Oliver Tale-Yazdi's avatar
      Lift dependencies to the workspace (Part 2/x) (#3366) · e89d0fca
      Oliver Tale-Yazdi authored 
      

Lifting some more dependencies to the workspace. Just using the
most-often updated ones for now.
It can be reproduced locally.

```sh
# First you can check if there would be semver incompatible bumps (looks good in this case):
$ zepter transpose dependency lift-to-workspace --ignore-errors syn quote thiserror "regex:^serde.*"

# Then apply the changes:
$ zepter transpose dependency lift-to-workspace --version-resolver=highest syn quote thiserror "regex:^serde.*" --fix

# And format the changes:
$ taplo format --config .config/taplo.toml
```

---------

Signed-off-by: default avatarOliver Tale-Yazdi <[email protected]>
      e89d0fca
    • Bastian Köcher's avatar
      Downgrade log message to `trace` (#3405) · ef6ac94f
      Bastian Köcher authored 
      This spams logs in `Debug` with no useful information.
      ef6ac94f
  17. Feb 19, 2024
  19. Feb 17, 2024
  21. Feb 16, 2024
  23. Feb 12, 2024
  25. Feb 11, 2024
  27. Feb 09, 2024
  29. Feb 08, 2024
  31. Feb 06, 2024
    • Andrei Eres's avatar
      subsystem-bench: Prepare CI output (#3158) · 9e6298e7
      Andrei Eres authored 
      

1. Benchmark results are collected in a single struct.
2. The output of the results is prettified.
3. The result struct used to save the output as a yaml and store it in
artifacts in a CI job.

```
$ cargo run -p polkadot-subsystem-bench --release -- test-sequence --path polkadot/node/subsystem-bench/examples/availability_read.yaml | tee output.txt
$ cat output.txt

polkadot/node/subsystem-bench/examples/availability_read.yaml #1

Network usage, KiB                     total   per block
Received from peers               510796.000  170265.333
Sent to peers                        221.000      73.667

CPU usage, s                           total   per block
availability-recovery                 38.671      12.890
Test environment                       0.255       0.085


polkadot/node/subsystem-bench/examples/availability_read.yaml #2

Network usage, KiB                     total   per block
Received from peers               413633.000  137877.667
Sent to peers                        353.000     117.667

CPU usage, s                           total   per block
availability-recovery                 52.630      17.543
Test environment                       0.271       0.090


polkadot/node/subsystem-bench/examples/availability_read.yaml #3

Network usage, KiB                     total   per block
Received from peers               424379.000  141459.667
Sent to peers                        703.000     234.333

CPU usage, s                           total   per block
availability-recovery                 51.128      17.043
Test environment                       0.502       0.167

```

```
$ cargo run -p polkadot-subsystem-bench --release -- --ci test-sequence --path polkadot/node/subsystem-bench/examples/availability_read.yaml | tee output.txt
$ cat output.txt
- benchmark_name: 'polkadot/node/subsystem-bench/examples/availability_read.yaml #1'
  network:
  - resource: Received from peers
    total: 509011.0
    per_block: 169670.33333333334
  - resource: Sent to peers
    total: 220.0
    per_block: 73.33333333333333
  cpu:
  - resource: availability-recovery
    total: 31.845848445
    per_block: 10.615282815
  - resource: Test environment
    total: 0.23582828799999941
    per_block: 0.07860942933333313

- benchmark_name: 'polkadot/node/subsystem-bench/examples/availability_read.yaml #2'
  network:
  - resource: Received from peers
    total: 411738.0
    per_block: 137246.0
  - resource: Sent to peers
    total: 351.0
    per_block: 117.0
  cpu:
  - resource: availability-recovery
    total: 18.93596025099999
    per_block: 6.31198675033333
  - resource: Test environment
    total: 0.2541994199999979
    per_block: 0.0847331399999993

- benchmark_name: 'polkadot/node/subsystem-bench/examples/availability_read.yaml #3'
  network:
  - resource: Received from peers
    total: 424548.0
    per_block: 141516.0
  - resource: Sent to peers
    total: 703.0
    per_block: 234.33333333333334
  cpu:
  - resource: availability-recovery
    total: 16.54178526900001
    per_block: 5.513928423000003
  - resource: Test environment
    total: 0.43960946299999537
    per_block: 0.14653648766666513
```

---------

Co-authored-by: default avatarAndrei Sandu <[email protected]>
      9e6298e7
    • Alin Dima's avatar
      prospective-parachains: respond with multiple backable candidates (#3160) · 7df1ae3b
      Alin Dima authored 
      Fixes https://github.com/paritytech/polkadot-sdk/issues/3129
      7df1ae3b
  33. Feb 05, 2024
    • Alexandru Gheorghe's avatar
      Introduce approval-voting/distribution benchmark (#2621) · f9f88688
      Alexandru Gheorghe authored 
      ## Summary
Built on top of the tooling and ideas introduced in
https://github.com/paritytech/polkadot-sdk/pull/2528, this PR introduces
a synthetic benchmark for measuring and assessing the performance
characteristics of the approval-voting and approval-distribution
subsystems.

Currently this allows, us to simulate the behaviours of these systems
based on the following dimensions:
```
TestConfiguration:
# Test 1
- objective: !ApprovalsTest
    last_considered_tranche: 89
    min_coalesce: 1
    max_coalesce: 6
    enable_assignments_v2: true
    send_till_tranche: 60
    stop_when_approved: false
    coalesce_tranche_diff: 12
    workdir_prefix: "/tmp"
    num_no_shows_per_candidate: 0
    approval_distribution_expected_tof: 6.0
    approval_distribution_cpu_ms: 3.0
    approval_voting_cpu_ms: 4.30
  n_validators: 500
  n_cores: 100
  n_included_candidates: 100
  min_pov_size: 1120
  max_pov_size: 5120
  peer_bandwidth: 524288000000
  bandwidth: 524288000000
  latency:
    min_latency:
      secs: 0
      nanos: 1000000
    max_latency:
      secs: 0
      nanos: 100000000
  error: 0
  num_blocks: 10
```

## The approach
1. We build a real overseer with the real implementations for
approval-voting and approval-distribution subsystems.
2. For a given network size, for each validator we pre-computed all
potential assignments and approvals it would send, because this a
computation heavy operation this will be cached on a file on disk and be
re-used if the generation parameters don't change.
3. The messages will be sent accordingly to the configured parameters
and those are split into 3 main benchmarking scenarios.

## Benchmarking scenarios

### Best case scenario *approvals_throughput_best_case.yaml*
It send to the approval-distribution only the minimum required tranche
to gathered the needed_approvals, so that a candidate is approved.

### Behaviour in the presence of no-shows *approvals_no_shows.yaml*
It sends the tranche needed to approve a candidate when we have a
maximum of *num_no_shows_per_candidate* tranches with no-shows for each
candidate.

### Maximum throughput *approvals_throughput.yaml*
It sends all the tranches for each block and measures the used CPU and
necessary network bandwidth. by the approval-voting and
approval-distribution subsystem.

## How to run it
```
cargo run -p polkadot-subsystem-bench --release -- test-sequence --path polkadot/node/subsystem-bench/examples/approvals_throughput.yaml
```

## Evaluating performance
### Use the real subsystems metrics
If you follow the steps in
https://github.com/paritytech/polkadot-sdk/tree/master/polkadot/node/subsystem-bench#install-grafana
for installing locally prometheus and grafana, all real metrics for the
`approval-distribution`, `approval-voting` and overseer are available.
E.g:
<img width="2149" alt="Screenshot 2023-12-05 at 11 07 46"
src="https://github.com/paritytech/polkadot-sdk/assets/49718502/cb8ae2dd-178b-4922-bfa4-dc37e572ed38">

<img width="2551" alt="Screenshot 2023-12-05 at 11 09 42"
src="https://github.com/paritytech/polkadot-sdk/assets/49718502/8b4542ba-88b9-46f9-9b70-cc345366081b">

<img width="2154" alt="Screenshot 2023-12-05 at 11 10 15"
src="https://github.com/paritytech/polkadot-sdk/assets/49718502/b8874d8d-632e-443a-9840-14ad8e90c54f">

<img width="2535" alt="Screenshot 2023-12-05 at 11 10 52"
src="https://github.com/paritytech/polkadot-sdk/assets/49718502/779a439f-fd18-4985-bb80-85d5afad78e2">

### Profile with pyroscope
1. Setup pyroscope following the steps in
https://github.com/paritytech/polkadot-sdk/tree/master/polkadot/node/subsystem-bench#install-pyroscope,
then run any of the benchmark scenario with `--profile` as the
arguments.
2. Open the pyroscope dashboard in grafana, e.g:
<img width="2544" alt="Screenshot 2024-01-09 at 17 09 58"
src="https://github.com/paritytech/polkadot-sdk/assets/49718502/58f50c99-a910-4d20-951a-8b16639303d9">



### Useful  logs
1. Network bandwidth requirements:
```
Payload bytes received from peers: 503993 KiB total, 50399 KiB/block
Payload bytes sent to peers: 629971 KiB total, 62997 KiB/block
```

2. Cpu usage by the approval-distribution/approval-voting subsystems.
```
approval-distribution CPU usage 84.061s
approval-distribution CPU usage per block 8.406s
approval-voting CPU usage 96.532s
approval-voting CPU usage per block 9.653s
```

3. Time passed until a given block is approved
```
 Chain selection approved  after 3500 ms hash=0x0101010101010101010101010101010101010101010101010101010101010101
Chain selection approved  after 4500 ms hash=0x0202020202020202020202020202020202020202020202020202020202020202
```

### Using benchmark to quantify improvements from
https://github.com/paritytech/polkadot-sdk/pull/1178 +
https://github.com/paritytech/polkadot-sdk/pull/1191

Using a versi-node we compare the scenarios where all new optimisations
are disabled with a scenarios where tranche0 assignments are sent in a
single message and a conservative simulation where the coalescing of
approvals gives us just 50% reduction in the number of messages we send.

Overall, what we see is a speedup of around 30-40% in the time it takes
to process the necessary messages and a 30-40% reduction in the
necessary bandwidth.

#### Best case scenario comparison(minimum required tranches sent).
Unoptimised
```
    Number of blocks: 10
    Payload bytes received from peers: 53289 KiB total, 5328 KiB/block
    Payload bytes sent to peers: 52489 KiB total, 5248 KiB/block
    approval-distribution CPU usage 6.732s
    approval-distribution CPU usage per block 0.673s
    approval-voting CPU usage 9.523s
    approval-voting CPU usage per block 0.952s
```

vs Optimisation enabled
```
   Number of blocks: 10
   Payload bytes received from peers: 32141 KiB total, 3214 KiB/block
   Payload bytes sent to peers: 37314 KiB total, 3731 KiB/block
   approval-distribution CPU usage 4.658s
   approval-distribution CPU usage per block 0.466s
   approval-voting CPU usage 6.236s
   approval-voting CPU usage per block 0.624s
```

#### Worst case all tranches sent, very unlikely happens when sharding
breaks.

Unoptimised
```
   Number of blocks: 10
   Payload bytes received from peers: 746393 KiB total, 74639 KiB/block
   Payload bytes sent to peers: 729151 KiB total, 72915 KiB/block
   approval-distribution CPU usage 118.681s
   approval-distribution CPU usage per block 11.868s
   approval-voting CPU usage 124.118s
   approval-voting CPU usage per block 12.412s
```

vs optimised
```
    Number of blocks: 10
    Payload bytes received from peers: 503993 KiB total, 50399 KiB/block
    Payload bytes sent to peers: 629971 KiB total, 62997 KiB/block
    approval-distribution CPU usage 84.061s
    approval-distribution CPU usage per block 8.406s
    approval-voting CPU usage 96.532s
    approval-voting CPU usage per block 9.653s
```


## TODOs
[x] Polish implementation.
[x] Use what we have so far to evaluate
https://github.com/paritytech/polkadot-sdk/pull/1191

 before merging.
[x] List of features and additional dimensions we want to use for
benchmarking.
[x] Run benchmark on hardware similar with versi and kusama nodes.
[ ] Add benchmark to be run in CI for catching regression in
performance.
[ ] Rebase on latest changes for network emulation.

---------

Signed-off-by: default avatarAndrei Sandu <[email protected]>
Signed-off-by: default avatarAlexandru Gheorghe <[email protected]>
Co-authored-by: default avatarAndrei Sandu <[email protected]>
Co-authored-by: default avatarAndrei Sandu <[email protected]>
      f9f88688
  35. Feb 02, 2024
  37. Jan 31, 2024
  39. Jan 30, 2024
  41. Jan 29, 2024